The composite cathode of a solid-state battery is a dense, non-porous blend of active material, conductive additive and a portion of solid electrolyte known as the catholyte. Unlike conventional lithium-ion cells, where a liquid electrolyte seeps into every pore, the solid-state version has no pore-filling liquid to rescue poor contacts. Every particle must touch its neighbour intimately, and both ions and electrons need homogeneous, percolating pathways through the electrode. The conductive additive in this study is Super C65, a carbon black from Imerys, which must form an unbroken electronic network threading through the cathode. The active material is carbon-coated lithium iron phosphate, or LFP, whose own carbon coating enhances intrinsic electronic conductivity and interfacial lithium transfer. The researchers were careful to distinguish between these two carbons: the factory-applied coating on the LFP particles and the C65 introduced during electrode processing behave very differently under the forces of mixing.

To isolate the effects of processing, the team prepared slurries under dry-room conditions with a dew point below minus 60 degrees Celsius, using a bead mill to first dissolve LiTFSI in acetonitrile and then mix in high molecular weight PEO to form the catholyte. The LFP and C65 powders were dry-mixed in a planetary vacuum mixer at 200, 750 or 1500 revolutions per minute, and the resulting powder blend was then wet-mixed into the catholyte for 60, 120 or 180 minutes. Five slurries were produced in total, each cast onto carbon-coated aluminium current collectors and dried under vacuum. Crucially, the researchers deliberately skipped calendering, the mechanical compaction step common in electrode manufacturing, so that the morphological fingerprints left by the mixing process itself would remain visible in the finished electrodes.

One of the study’s most elegant methodological contributions is the introduction of a relative viscosity parameter. Batch-to-batch variability in the PEO raw material, stemming from differences in molecular weight distribution, meant that absolute viscosity measurements could not be compared reliably across samples. By normalizing the slurry viscosity to the viscosity of the corresponding catholyte at the end of its own mixing, the team could decouple the true effects of mixing time and speed from uncontrolled fluctuations in the polymer feedstock. Validation experiments with four separate preparations, including three different PEO batches, confirmed that this normalization substantially reduced variability, offering a practical tool that other laboratories can adopt to make their slurry comparisons meaningful.

The rheological results revealed a counterintuitive trend. Longer wet mixing times and higher dry mixing speeds both reduced slurry viscosity, and the researchers traced this not to further polymer degradation but to the progressive deagglomeration of the carbon black. Gel permeation chromatography showed that the PEO molecular weight decreased exponentially toward a plateau, with an apparent scission-rate constant of 7.49 times ten to the minus seven per minute, but since total mixing times stayed below the point where degradation becomes negligible, the viscosity drop had to come from elsewhere. As C65 agglomerates break apart, the number of carbon particles rises, promoting immobilization of polymer chains and reducing chain entanglement, a mechanism previously described by Hoffman and colleagues. More effective deagglomeration also increases interparticle volume, allowing more solvent molecules to occupy the spaces between carbon particles and thereby lowering the suspension viscosity.

These rheological differences translated directly into electrode microstructure. Scanning electron microscopy of surfaces and argon ion-milled cross-sections, analysed with ImageJ, showed that longer wet mixing produced electrodes with lower porosity, higher active material loading and fewer surface lumps, because lower viscosity allows better particle rearrangement and compaction during drying. In the dry mixing series, the sample processed at 1500 rpm displayed the most homogeneous morphology, while the 200 rpm sample exhibited a highly cracked surface, suggesting that large C65 agglomerates weaken the mechanical integrity of the composite cathode and hinder uniform polymer distribution. Porosity values ranged from about 1.65 percent for the longest wet mixing time to nearly 3 percent for the mildest conditions, differences that proved consequential for transport properties.

Electronic and ionic conductivity measurements told a more nuanced story. Reference pellets containing as little as 5 weight percent C65 achieved electronic conductivities of roughly ten to the minus two siemens per centimetre, confirming that this modest carbon fraction is sufficient for percolation. Yet after full electrode processing, bulk electronic conductivity dropped by nearly two orders of magnitude at both 25 and 70 degrees Celsius. Wet mixing time had little effect on this bulk conductivity, but in-plane resistivity measurements revealed that excessive wet mixing stresses the carbon particles and degrades the conductive network. In the dry mixing series, the intermediate 750 rpm condition delivered the lowest interfacial resistance and the highest ionic conductivity, while the 1500 rpm sample, despite its denser packing, showed signs of carbon particles being over-stressed and unable to form an optimal network.

Full-cell testing in monolayer pouch cells with lithium metal anodes, cycled at 70 degrees Celsius between 2.6 and 3.7 volts, exposed the trade-offs with striking clarity. At the gentle C/20 rate, all cells delivered similar capacities between 156 and 158 mAh per gram, but at higher rates the mildest processing conditions won out: the 60-minute wet mix and the 200 rpm dry mix, both with the highest slurry viscosities and highest porosities, achieved the highest capacities at C/5. The researchers attribute this to the higher viscosity limiting conductive additive redistribution, thereby preserving a favourable electronic network, while mud cracking in the 200 rpm electrode may have created preferential channels for solid electrolyte infiltration during cycling. However, these high-capacity electrodes also showed the poorest cycle life, with the 200 rpm sample lasting only 65 cycles before coulombic efficiency fell below 98 percent, compared to 120 cycles for the balanced 750 rpm condition.

The degradation mechanism was revealed through X-ray computed micro-tomography of intact pouch cells, a technique that avoids the impossible task of disassembling strongly adhesive cycled cells. Cross-sections of a pristine cell showed homogeneous layers with only minor pores at the cathode-electrolyte interface, but after 130 cycles the lithium metal anode had thinned from 500 to 470 micrometres, voids had multiplied in the cathode, and dark regions appeared within the solid electrolyte layer, signatures of lithium dendrites growing from the anode through the polymer. Grain boundaries in the electrolyte, attributed to solid electrolyte interphase formed by soft dendrites, were also visible. Impedance spectroscopy of the aged cell confirmed diminished ionic diffusion, tying the loss of coulombic efficiency directly to dendrite propagation.

The broader lesson of this work is that in solid-state batteries, processing is not a secondary consideration but a first-order design variable. The optimal wet mixing time of 120 minutes balanced electrode compaction against preservation of the conductive network, while an intermediate dry mixing speed of 750 rpm achieved the best cyclability without compromising lithium-ion transport. Even a small amount of residual porosity, the authors suggest, may serve as stress-relief space accommodating the volume changes of lithium insertion and extraction in a mechanically rigid system. As solid-state batteries edge toward commercialization, this study demonstrates that the path to better cells may run through the mixing vessel, where the fate of every carbon black agglomerate ultimately determines whether electrons and ions can find their way home.

Subject of Research: Effect of slurry mixing parameters on carbon black distribution and performance of solid polymer electrolyte composite cathodes

Article Title: Carbon black distribution in low viscosity polymer slurries

Article References: Carbon black distribution in low viscosity polymer slurries. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: solid-state batteries, carbon black, polymer electrolyte, slurry rheology, composite cathode, lithium metal anode, PEO, LiTFSI, electrode processing, lithium dendrites, X-ray tomography, LFP

The research team, led by Kwame Ankomah with David Azanu and Mwema Felix Mwema, followed the internationally recognized ISO 14040 and ISO 14044 standards for life cycle assessment. Rather than examining a single factory or a single pollutant, the method traces every input and output associated with a defined unit of production. In this case, the functional unit was 100,000 polyethylene carrier bags manufactured per year, weighing 750 kilograms in total. That figure reflects the scale of small and medium-sized recycling operations that have sprung up across Ghana, where plastic waste collection and reprocessing have become both an environmental necessity and a source of livelihood.

The system boundary of the analysis covered the manufacturing phase along with the upstream burdens of the materials and energy that feed it. Electricity consumption, sodium nitrate, and carbon black production were all included, with background data drawn from the Ecoinvent 3.11 database, one of the most widely used life cycle inventory resources in the world. The impact assessment was carried out in SimaPro 10.2.0.3 using the ReCiPe 2016 Midpoint (H) methodology for a world-scale characterization, which allowed the team to quantify eighteen separate impact categories, ranging from global warming and fossil resource depletion to human toxicity, freshwater ecotoxicity, and particulate matter formation.

The headline finding is stark: electricity is the dominant contributor to most of the impact categories examined. Ghana’s national grid currently relies on thermal generation for 66.4 percent of its supply, hydropower for 32.9 percent, and renewables for a mere 0.7 percent. That mix means every kilowatt-hour consumed by an extruder or a pelletizer carries a substantial fossil signature. For the annual production of 100,000 recycled bags, electricity alone accounted for 288.9 kilograms of carbon dioxide equivalent out of a total global warming potential of 353.53 kilograms. In other words, more than four-fifths of the climate impact of making recycled carrier bags in Ghana comes from the power they consume during manufacturing.

The pattern repeats across other environmental dimensions. Electricity was responsible for 137.2 kilograms of 1,4-dichlorobenzene equivalent in terrestrial ecotoxicity, out of a total of 264.5 kilograms, and for 106.3 kilograms of oil equivalent in fossil resource scarcity, out of a total of 131.3 kilograms. These numbers matter because they reframe the debate about recycling in developing economies. The recycled feedstock itself avoids the virgin polymer production that would otherwise dominate a conventional life cycle, yet the downstream processing can erode those gains if the energy supply remains carbon-intensive.

Chemical additives emerged as a second, more subtle tier of environmental burden. Sodium hydroxide, used in wastewater treatment at the recycling facility, was the second-largest contributor to global warming, adding 26.0 kilograms of carbon dioxide equivalent. Carbon black, the pigment that gives many carrier bags their familiar dark color, ranked second for fossil resource scarcity at 13.7 kilograms of oil equivalent. Meanwhile, sodium hydroxide and polyaluminium chloride, both employed to treat process wastewater, were significant contributors to toxicity categories. These chemicals are often overlooked in public discussions of plastic recycling, which tend to focus on collection rates and sorting efficiency, yet they represent a meaningful share of the total footprint and a clear target for optimization.

To test how sensitive the results were to the energy assumption, the researchers ran a sensitivity analysis comparing Ghana’s actual grid with a solar tower energy scenario. The difference was dramatic. Switching to concentrated solar power reduced the global warming potential of the annual bag production by approximately 74 percent, from 353.5 kilograms of carbon dioxide equivalent down to 92.0 kilograms. Reductions of similar magnitude appeared across most of the other impact categories, since fossil combustion is implicated not only in climate change but also in particulate formation, acidification, and resource depletion. The result demonstrates that the environmental performance of recycling operations is not fixed by the recycling process itself but by the energy system in which it is embedded.

The implications extend well beyond Ghana. Many sub-Saharan African countries share a similar profile: growing plastic waste streams, emerging recycling industries, and electricity grids dominated by thermal generation. In such contexts, the environmental case for recycling depends heavily on parallel investments in clean energy. A recycling plant connected to a decarbonized grid can deliver genuine circular economy benefits, diverting waste from open dumps and waterways while avoiding the emissions of virgin plastic production. The same plant connected to a coal- or gas-heavy grid may deliver far smaller net gains than policymakers assume.

The study also highlights the practical value of life cycle assessment as a decision-making tool for emerging industries. By quantifying eighteen impact categories at the midpoint level, the analysis gives plant operators and regulators a granular map of where environmental burdens arise. The findings point to two concrete levers: energy decarbonization, whether through grid greening or on-site renewable generation, and additive optimization, including reducing chemical inputs in wastewater treatment and reconsidering pigment choices such as carbon black. Neither lever requires rethinking the fundamental recycling process, which makes them attractive targets for near-term improvement.

As plastic production continues to rise globally and developing economies grapple with mounting waste, studies like this one provide a necessary corrective to simplistic narratives. Recycling is essential, but its benefits are contingent. In Ghana, the path to genuinely sustainable plastic recycling runs directly through the national grid, and the faster that grid sheds its fossil intensity, the closer the country’s circular economy ambitions come to delivering the environmental dividends they promise.

Subject of Research: Life cycle assessment of recycled polyethylene carrier bag manufacturing in Ghana

Article Title: Life cycle assessment of polyethylene carrier bags manufactured from recycled plastics in Ghana: Environmental impacts of chemical additives and a fossil-intensive electricity grid

Article References: Ankomah, K., Azanu, D., & Mwema, M. F. (2026). Life cycle assessment of polyethylene carrier bags manufactured from recycled plastics in Ghana: Environmental impacts of chemical additives and a fossil-intensive electricity grid. PLOS Sustainability and Transformation, 5(8), e0000259. https://doi.org/10.1371/journal.pstr.0000259

Image Credits: AI Generated

DOI: 10.1371/journal.pstr.0000259

Keywords: life cycle assessment, plastic recycling, polyethylene carrier bags, Ghana, electricity grid, carbon footprint, solar power, carbon black, sodium hydroxide, circular economy, ReCiPe 2016, sub-Saharan Africa

The synthesis itself is strikingly simple. One gram of guaraná seed material was soaked in 100 milliliters of distilled water for 24 hours, filtered, and stored cold. When 50 milliliters of a dilute silver nitrate solution were mixed with a small aliquot of this extract, the reaction medium changed from colorless to yellowish-brown within minutes, the classic visual signature of colloidal silver forming. Ultraviolet-visible spectroscopy confirmed the transformation, revealing a surface plasmon resonance band at 418 to 420 nanometers, the optical fingerprint of silver nanoparticles. The plasmon intensity grew over the first two hours, indicating ongoing nanoparticle formation, before shifting slightly toward 410 nanometers, a change the authors interpret cautiously as evidence of evolving colloidal populations rather than proof of any specific particle shape.

Why guaraná? The seeds of P. cupana are rich in caffeine, phenolics, and other redox-active metabolites, compounds that previous phytochemical studies have identified in guaraná-derived matrices. The authors are careful to note that the extract was not chromatographically profiled in this study, so these constituents are cited as literature-supported candidate reducing and stabilizing agents rather than directly measured ones. Still, the chemistry is plausible: plant phenolics can reduce silver ions to metallic silver while simultaneously adsorbing onto particle surfaces, providing an organic corona that helps keep the colloid dispersed. After testing different temperatures and pH values, the team settled on pH 9.0 at 30 degrees Celsius as the optimal working condition for subsequent preparations.

Dynamic light scattering painted a nuanced picture of the resulting colloid. The mean hydrodynamic diameter came out at 429.5 plus or minus 14.0 nanometers, with a polydispersity index of 0.229, indicating a moderately polydisperse system rather than a uniform one. The intensity-weighted distribution actually contained two populations: a minor population centered at 21.7 nanometers accounting for roughly 2 percent of the scattered-light intensity, and a dominant population near 452 nanometers making up the remaining 98 percent. Because light scattering is intensity-weighted, larger entities dominate the signal even when they represent a small fraction of the particle count. The authors therefore interpret the large value as the hydrodynamic size of hydrated, associated colloidal entities, metallic domains wrapped in extract-derived organic material, rather than the size of individual silver cores. The zeta potential of minus 10.93 millivolts, modest in magnitude, suggests limited electrostatic repulsion, with steric stabilization from the organic corona likely helping the dispersion persist.

To make the nanoparticles electrochemically useful, the team immobilized the silver phase onto Vulcan XC-72R carbon black using two routes. In the in situ route, the carbon was present during nanoparticle formation; in the ex situ route, pre-formed nanoparticles were combined with carbon afterward. Ultraviolet-visible analysis of the supernatants showed a marked suppression of the plasmon band after contact with the support, consistent with retention of the silver-containing phase on the carbon surface. X-ray diffraction patterns were dominated by the broad carbon reflections at 24.5 and 43.7 degrees two-theta, with a weak additional reflection near 37.9 degrees assigned to a silver-containing phase, supportive but not exhaustive evidence of immobilization. Scanning electron microscopy showed that both materials preserved the particulate morphology of the carbon support, while energy-dispersive X-ray spectroscopy detected carbon, oxygen, and a low but detectable silver signal. Transmission electron microscopy in dark-field mode revealed high-contrast nanodomains distributed across the carbon matrix, tentatively associated with the silver phase.

Textural measurements added an important control dimension. Pristine Vulcan carbon displayed a specific surface area of 150.73 square meters per gram, while the in situ and ex situ composites measured 131.10 and 133.04 square meters per gram respectively, with pore diameters remaining in a narrow 2.03 to 2.18 nanometer range. The key insight is that the two supported materials are texturally almost identical yet electrochemically distinct, which means their different behaviors cannot be explained by gross porosity differences and likely reflect route-dependent interfacial organization, how the silver and organic residues are arranged at the surface.

The electrochemical experiments used the commercial emulsifiable concentrate Decis 25 EC, a Bayer product containing 25 grams per liter of deltamethrin, as the pesticide source. Deltamethrin is a synthetic pyrethroid widely used against insect pests, but its environmental persistence and potential effects on non-target organisms have raised toxicological concern, making detection methods valuable. The researchers deposited their AgNPs@C materials onto polished gold disk electrodes and ran cyclic voltammetry at scan rates from 0.01 to 0.30 volts per second in pH 8.0 phosphate buffer with potassium chloride. In blank electrolyte, the ex situ material showed a better-resolved anodic process around 1.0 volt and a corresponding cathodic process between 0.9 and 0.8 volts, tentatively associated with silver redox chemistry, while the in situ material gave a broader response with a stronger capacitive contribution.

In the presence of the deltamethrin formulation, both materials exhibited two irreversible cathodic processes. For the ex situ composite, the peaks appeared near 0.42 and 0.55 volts versus a normal hydrogen electrode, with currents of approximately minus 3.556 and minus 4.491 milliamperes. The in situ material showed peaks near 0.32 and 0.60 volts, with a substantially stronger first cathodic response of about minus 16.177 milliamperes. Regression analysis of peak current against scan rate and the square root of scan rate showed that the latter relationships were generally more linear, particularly for the second cathodic process, indicating diffusion-influenced transport rather than ideal surface-confined behavior. The authors stress an important interpretive caveat: because a commercial emulsifiable concentrate was used rather than analytical-grade deltamethrin, the voltammograms reflect the behavior of the whole formulation, coformulants included, in the presence of the electrode material. The study is therefore framed as a comparative behavior investigation at a fixed formulation concentration, not as analytical validation of a deltamethrin sensor.

The biological half of the study revealed a different kind of duality. In germination bioassays, gherkin (Cucumis anguria) and coriander (Coriandrum sativum) seeds were exposed to the aqueous guaraná extract and the biosynthesized nanoparticle dispersions at low (0.1 percent) and high (1.0 percent) concentrations, with distilled water and a Tween vehicle as controls. Each treatment comprised three replicates of 25 surface-disinfected seeds maintained for 14 days under a 12-hour dark and light photoperiod, with germination scored daily and root length measured at the end. The parameters tracked included germination percentage, mean germination time, mean germination rate, germination rate index, and mean root length, with statistical analysis by ANOVA followed by the Student–Newman–Keuls test.

The results were clearly concentration- and species-dependent. For gherkin, the low-dose nanoparticle treatment maintained high germination and a higher germination rate index than the extract treatments, while the high-dose nanoparticle treatment caused a marked reduction in final germination. Coriander followed a different pattern: the low-dose extract remained comparable to the controls, whereas both high-dose treatments were clearly inhibitory. Root growth data reinforced the trend, with the strongest negative effects associated with the highest nanoparticle concentration, especially for coriander. Notably, the low nanoparticle dose was in some cases compatible with a more favorable early response than the corresponding extract treatment alone. Because the dispersions were applied as complete systems, the authors interpret these effects as properties of the dispersions as applied rather than attributing them exclusively to an isolated nanoparticulate fraction. The findings align with a broader literature in which silver nanoparticles can either stimulate or impair germination depending on dose, particle properties, and plant species, ranging from biostimulation to phytotoxicity. Taken together, the study positions guaraná-mediated silver nanoparticles as green multifunctional materials, one part sustainable synthesis, one part pesticide-relevant electrochemistry, and one part dose-sensitive biology, while leaving open the question of which interfacial and molecular mechanisms underlie each response.

Subject of Research: Green synthesis of guaraná-mediated silver nanoparticles for electrochemical response to deltamethrin and effects on seed germination

Article Title: Green synthesized silver nanoparticles mediated by Paullinia cupana extract exhibit electrochemical behavior toward a commercial deltamethrin formulation and concentration related effects on seed germination

Article References: da Encarnação, J. R., Flores, S. M., da Silva, E. M., Ribeiro, C. R., de Souza, E. A., Neiva, E. G. C., Perotti, G. F., & Maia, P. J. S. (2026). Green synthesized silver nanoparticles mediated by Paullinia cupana extract exhibit electrochemical behavior toward a commercial deltamethrin formulation and concentration related effects on seed germination. Discover Chemistry, 3(1), Article 483. https://doi.org/10.1007/s44371-026-00946-5

Image Credits: AI Generated

DOI: 10.1007/s44371-026-00946-5

Keywords: silver nanoparticles, green synthesis, Paullinia cupana, guaraná, deltamethrin, electrochemistry, cyclic voltammetry, carbon black, seed germination, phytotoxicity, nanotechnology, pyrethroid

Ticagrelor is a mainstay of modern cardiology. It works by reversibly blocking the platelet P2Y12 receptor, which prevents adenosine diphosphate from activating platelets and triggering the clotting cascade. Physicians prescribe it, often alongside aspirin, to patients with acute coronary syndrome or ST-segment elevation myocardial infarction to ward off further thrombotic events. Because the drug’s therapeutic effect depends on careful dosing and because patients differ widely in how they metabolize it, analytical methods that can measure ticagrelor quickly and accurately are clinically valuable. Until now, that job has mostly fallen to chromatography-based techniques such as high-performance liquid chromatography, liquid chromatography coupled with mass spectrometry, reverse-phase HPLC, and various spectrophotometric and bio-analytical approaches. These methods are accurate but typically require expensive instrumentation, trained operators, lengthy sample preparation, and centralized laboratory facilities.

Electrochemical sensing offers an appealing alternative. By translating molecular interactions at an electrode surface into an electrical current, such sensors can be fast, cheap, portable, and sensitive. The catch is that a bare electrode rarely provides enough signal for trace-level detection of a drug in a complex biological matrix. The standard remedy is to coat the electrode with a nanomaterial or nanocomposite that boosts conductivity, surface area, and catalytic activity. The Iranian-led team behind the new study chose an unusual pairing: carbon black, an abundant and highly conductive industrial carbon, and a silver-based metal-organic framework, a crystalline coordination network built from silver ions and the organic linker 1,3,5-benzenetricarboxylic acid.

Each component brings distinct strengths. Carbon black offers excellent porosity, high surface area, strong electrical conductivity, and a wide potential window, making it an ideal conductive backbone. Metal-organic frameworks, meanwhile, are prized for their enormous surface areas, tunable structures, and high porosity, all of which improve the interface between electrode and electrolyte. In this system, the silver framework performs three critical jobs: it supplies metal-based catalytic activity, it acts as an intrinsic electrochemical signal source through its own silver-related redox chemistry, and its tunable porosity facilitates molecular diffusion while enlarging the effective surface area available for recognition events. The researchers synthesized the framework by dissolving the organic linker and silver nitrate separately in methanol, combining the solutions, and heating the mixture at 120 degrees Celsius overnight, a straightforward and economical preparation.

Microscopy and spectroscopy confirmed that the marriage worked. Field-emission scanning electron microscopy showed carbon black forming a spherical film-like coating, while the silver framework appeared as sheet-like crystals with sharp, regular morphologies. In the composite, the two components merged into a porous, spongy, interconnected architecture with no phase separation, exactly the kind of structure that maximizes both conductivity and accessible surface area. Energy-dispersive X-ray analysis and elemental mapping verified that carbon, oxygen, nitrogen, and silver were uniformly distributed throughout the material. Fourier-transform infrared spectroscopy revealed characteristic bands from the aromatic linker and carboxylate groups, and X-ray diffraction showed that the framework’s crystalline structure survived composite formation intact, with no detectable separate crystalline silver oxide or metallic silver impurity phases.

Electrochemical tests then revealed why the composite outperforms its ingredients. Using cyclic voltammetry and electrochemical impedance spectroscopy with a ferricyanide redox probe, the team found that adding carbon black to a glassy carbon electrode increased current and lowered charge-transfer resistance from 687 ohms for the bare electrode to 344 ohms. The silver framework alone, hampered by its intrinsically low conductivity, actually raised resistance to 2016 ohms. But the combined composite slashed resistance to just 221 ohms, clear evidence of synergy. Calculations based on the Randles-Sevcik equation showed the composite electrode’s electrochemically active surface area reached 0.045 square centimeters, more than double the 0.021 square centimeters of the bare electrode.

Perhaps the most intriguing finding concerns how the sensor actually detects ticagrelor. Neither the bare electrode nor the carbon-black-modified electrode produced a distinct response to the drug. Instead, the signal originates from the silver-containing framework itself: the drug, with its sulfur-, nitrogen-, and oxygen-containing functional groups, accumulates on the electrode through affinity interactions with accessible silver sites and hydrogen bonding with the organic linker, thereby blocking the electroactive silver sites and suppressing the silver-related current. The result is an indirect, signal-off mechanism in which the drug’s presence is measured by how much it dampens the baseline signal. Carbon black amplifies this effect dramatically. The drug-induced current change was approximately 519 microamperes at the composite electrode versus 196 microamperes at the framework alone, a roughly 2.6-fold enhancement, because the conductive carbon network improves electron transfer between the electroactive silver sites and the underlying electrode while also dispersing the framework particles more effectively.

After optimizing the composite ratio, buffer pH, and salt concentration, the sensor delivered striking analytical performance. Differential pulse voltammetry yielded a linear response across an extraordinarily wide concentration range spanning 0.01 to 2500 nanomolar, with a correlation coefficient of 0.9983 and a calculated detection limit of 0.0033 nanomolar. For comparison, previously reported ticagrelor sensors based on carbon paste electrodes modified with multiwalled carbon nanotubes and titanium nanoparticles, zeolite-modified carbon paste, or solid gold electrodes achieved detection limits in the hundreds of nanomolar to micromolar range. The authors caution that such cross-study comparisons should be interpreted carefully, since electrode architectures, sample preparation, and detection-limit calculations differ, but the numbers nonetheless underline the platform’s analytical promise. Microscopy before and after testing also confirmed the composite’s structural stability under operating conditions.

The sensor proved robust in the ways that matter for real-world use. It tolerated high concentrations of structurally related drugs and common biological interferents, including ticlopidine, clopidogrel, warfarin, ascorbic acid, dopamine, uric acid, and glucose. Five identical electrodes produced responses with a relative standard deviation of just 2.5 percent, and five repeated measurements on a single electrode gave 3.1 percent. After fifteen days of storage at room temperature, the electrode retained 93 percent of its initial response, and fifty consecutive voltammetric cycles preserved 95.32 percent of the original signal. Most importantly, when the team spiked human serum samples with 50, 100, and 200 nanomolar ticagrelor after protein precipitation, the sensor recovered between 99.5 and 101.2 percent of the added drug with relative standard deviations below 2.8 percent, demonstrating that the platform can function in a genuine biological matrix rather than only in pristine buffer solutions.

The broader significance of the work lies in its demonstration that cheap, readily available materials can be engineered into sensors rivaling far costlier analytical instruments. Carbon black costs pennies, the silver framework is synthesized in a single overnight reaction, and the entire electrode modification involves ultrasonicating the two powders in a drop of solvent and drying five microliters onto a glassy carbon electrode. A sensor built this way could, in principle, support point-of-care or bedside monitoring of ticagrelor, helping clinicians tailor antiplatelet therapy to individual patients and detect abnormal drug levels before they translate into bleeding or clotting complications. The signal-off design, in which the analyte suppresses a built-in silver redox signal, also offers a template that other researchers could adapt to different drug molecules capable of binding silver sites. While further validation in larger clinical studies would be needed before any diagnostic deployment, the study adds a compelling entry to the growing toolkit of metal-organic framework sensors and shows how the right nanoscale partnership can turn an ordinary electrode into an extraordinarily perceptive one.

Subject of Research: Electrochemical detection of the antithrombotic drug ticagrelor using a silver metal-organic framework and carbon black nanocomposite-modified electrode

Article Title: Electrochemical sensor based on Ag-metal organic framework/carbon black nanocomposite for the selective detection of Ticagrelor

Article References: Roushani, M., Karazan, Z. M., & Makki, I. S. (2026). Electrochemical sensor based on Ag-metal organic framework/carbon black nanocomposite for the selective detection of Ticagrelor. Results in Chemistry, 31, Article 103939. https://doi.org/10.1016/j.rechem.2026.103939

Image Credits: AI Generated

DOI: 10.1016/j.rechem.2026.103939

Keywords: ticagrelor, electrochemical sensor, metal-organic framework, carbon black, nanocomposite, glassy carbon electrode, antithrombotic drug, differential pulse voltammetry, human serum, detection limit, silver framework, P2Y12 receptor

The research, led by Rachida Idir of Cerema and University Gustave Eiffel together with colleagues from the University of Montpellier’s LMGC laboratory and IMT Mines Alès, including Katerina Ioannidou and Gwenn Le Saout, examined two commercially important types of carbon black in cement pastes. The first, furnace black, is the industrial standard, produced by partially burning heavy petroleum feedstocks in controlled furnaces. The second, acetylene black, is made by decomposing acetylene gas and is prized for its high purity and distinctive structure. The team varied the amount of carbon black, the water-to-cement ratio, and the dosage of superplasticizer, the chemical admixture used to keep workable concrete flowing without excess water, to map out how each parameter shaped the electrical behavior of the resulting paste.

The physics at the heart of the work is the percolation threshold, a concept borrowed from statistical physics that describes when disconnected particles suddenly link up into a continuous network. Ordinary cement paste is a poor conductor, relying mostly on ions dissolved in its pore water to carry current. Dispersed carbon black particles change that. Below a critical loading, the particles remain isolated islands, and the paste barely conducts better than before. Once that threshold is crossed, conductive pathways snake through the matrix and resistance plummets. In these experiments, the threshold generally appeared around 2 percent carbon black by weight of cement, and conductivity values above 1 siemens per meter, a level useful for practical sensing and heating applications, were typically reached at dosages of about 3 to 4 percent.

Under the conditions tested, acetylene black proved more effective than furnace black at building these conductive networks. That advantage matters because it means less additive is needed to reach a target conductivity, which in turn reduces both the material cost and the environmental footprint of the composite. The finding aligns with a growing body of literature on carbon-modified cementitious materials, which has explored everything from carbon nanotubes and nanofibers to carbon fibers and graphite as conductive fillers. Carbon black occupies an attractive middle ground in that landscape: it is far cheaper than nanotubes, easier to disperse than many high-aspect-ratio fillers, and available at industrial scale, making it a realistic candidate for construction applications where cost per cubic meter is decisive.

Conductive cement is not a laboratory curiosity. Researchers have already demonstrated electrically heated pavement systems that keep airport runways ice-free without salt, and self-sensing composites whose electrical resistance shifts as cracks form or loads change, allowing structures to report their own health. The piezoresistive effect in carbon-loaded cement means that squeezing the material alters its conductivity, so a bridge deck embedded with such sensors could, in principle, flag overloads or hidden damage continuously. Joule heating, where current passing through the resistive material generates warmth, underpins the deicing concept. What has been missing from many of these demonstrations is a rigorous accounting of the climate burden that the conductive additive adds to an already carbon-intensive material.

That accounting is the second pillar of the new study. The team performed a life cycle assessment focused on the global warming potential, or GWP, of the paste formulations, considering both the production of the carbon black itself and the full paste recipe. At the scale of the raw materials, the differences between acetylene black and furnace black were significant, reflecting the very different industrial processes behind them. But once the analysis moved to the scale of the complete paste, those differences shrank dramatically. The reason is sobering: cement clinker production, with its limestone calcination and kiln fuel emissions, so dominates the carbon footprint of the paste that the choice between two carbon blacks becomes a secondary consideration. Cement remained the overwhelming contributor to GWP across all formulations.

To connect functionality with climate impact in a single metric, the researchers introduced a novel indicator they call the Performance Impact Indicator, or PII, defined as the ratio of global warming potential to electrical conductivity. This simple ratio captures a design tension: adding more carbon black raises the GWP of the paste, but it also raises conductivity, and the question is which effect wins. The experiments delivered a counterintuitive and encouraging answer. Higher carbon black contents led to lower PII values, meaning that the conductivity gains outpaced the added emissions. In other words, once past the percolation threshold, each additional increment of carbon black buys more electrical performance per unit of climate impact, at least within the range investigated. For designers of smart concrete, this suggests that under-dosing the filler may be the worst of both worlds, delivering neither strong conductivity nor an efficient carbon-to-performance trade.

The study also looked beyond conventional supply chains to two alternative routes for producing carbon black, examining them from an environmental perspective. The first is a process associated with hydrogen co-production, in which methane is pyrolyzed, splitting natural gas into solid carbon and hydrogen gas rather than burning it. This route, sometimes linked to so-called turquoise hydrogen, has attracted attention as a way to produce both a low-carbon fuel and carbon black with potentially far lower emissions than the furnace process. The second alternative is based on waste tire pyrolysis, in which end-of-life tires are heated in the absence of oxygen to recover oil, gas, steel, and a recycled carbon black. Both scenarios suggest that lower-impact carbon black supply routes may deserve serious consideration for conductive cement applications, potentially decoupling the growth of smart concrete from additional fossil feedstock consumption while giving waste tires a second life.

The broader significance of the work lies in its framing. Multifunctional materials are often evaluated on performance alone, with sustainability treated as an afterthought or a marketing claim. By pairing systematic electrical measurements with life cycle thinking, and by proposing a metric that binds the two together, the French team offers a template for how emerging construction technologies should be assessed. The PII approach echoes earlier eco-efficiency work in cement science, which sought to measure how much functional service a structure delivers per unit of environmental burden. Applying that logic to conductive cement reveals a genuinely useful insight: the environmental case for these materials improves as the conductive network matures, provided the dosage is chosen wisely.

Challenges remain before carbon-black cement becomes a routine building material. Dispersion of nanoparticles in the harsh, alkaline environment of fresh cement is notoriously difficult, and researchers continue to explore techniques such as sonication and optimized admixture chemistry to achieve uniform networks. Durability over decades of weathering, long-term stability of the conductive pathways, and the cost of scaling up alternative carbon black production routes all require further study. The authors also note that their environmental comparison at the paste scale was limited to the GWP indicator, leaving other impact categories for future work. Yet the direction of travel is clear. As infrastructure ages and cities demand smarter, more resilient materials, cement that can carry both loads and current may find its place, and this study shows that the greenest version of that future depends not just on what goes into the concrete, but on where its carbon comes from.

Subject of Research: Conductive cement pastes modified with carbon black and their electrical performance and global warming potential

Article Title: Carbon black from multiple production routes in conductive cement pastes: balancing multifunctional performance and environmental burden

Article References: Idir, R., Souane, S. F., Touati, F., Ioannidou, K., & Le Saout, G. (2026). Carbon black from multiple production routes in conductive cement pastes: balancing multifunctional performance and environmental burden. Journal of Industrial Ecology, 30(4), 2071-2088. https://doi.org/10.1007/s44498-026-00140-x

Image Credits: AI Generated

DOI: 10.1007/s44498-026-00140-x

Keywords: carbon black, conductive cement, cement paste, percolation threshold, electrical conductivity, life cycle assessment, global warming potential, furnace black, acetylene black, waste tire pyrolysis, turquoise hydrogen, smart materials

To understand why this result matters, it helps to distinguish supercapacitors from the lithium-ion batteries that dominate consumer electronics. Batteries store large amounts of energy through slow chemical reactions, which is why they take hours to charge and degrade over hundreds or thousands of cycles. Supercapacitors, by contrast, store energy electrostatically, in the electric field that forms at the interface between an electrode and an electrolyte. They hold relatively small amounts of energy compared with batteries, but they take that energy in and release it extremely rapidly, and in some designs they can survive millions of charge-discharge cycles without significant degradation. That combination of speed and durability makes them attractive for applications where power is needed in short, repeated bursts rather than as a long-duration reserve. For a building fitted with solar panels, supercapacitors embedded in the structure could absorb surges of renewable electricity as they arrive and discharge them on demand, smoothing the mismatch between when energy is generated and when it is actually used.

The central challenge in turning cement into a supercapacitor is that ordinary concrete is a poor electrical conductor. Cement hydrates into a porous, mineral-rich matrix that is excellent at bearing compressive loads but terrible at shuttling electrons and ions. The research team’s solution was to build conductivity directly into the material. They mixed carbon nanotubes, carbon black, and cement together to form a printable electrode ink. Carbon nanotubes are cylindrical structures of carbon atoms just nanometers in diameter, renowned for their exceptional electrical conductivity and mechanical strength. Carbon black, a much cheaper amorphous form of carbon, provides additional conductive pathways and helps form a percolating network throughout the composite. Blended into wet cement, these carbon additives transform the paste from an insulator into an electrode material, while the cement itself continues to cure and harden much as it would in any construction application.

Geometry proved to be just as important as chemistry. Using a 3D printer, the team deposited the electrode ink onto a small concrete slab in a pattern resembling interlocked fingers, a configuration known in electrochemistry as an interdigitated electrode design. In this arrangement, two sets of parallel electrode fingers alternate with one another, like the interlaced fingers of two hands held together without touching. The significance of this geometry lies in the distance that charged ions must travel. In a conventional two-plate capacitor, ions in the electrolyte have to migrate across the entire gap separating the electrodes, which slows the device down and wastes energy as internal resistance. With interdigitated electrodes, every finger of one polarity sits immediately adjacent to fingers of the opposite polarity, so ions move only short distances laterally. As the researchers note, this shortened travel distance made the overall supercapacitor more efficient than previous iterations of cement-based energy storage, which had struggled with exactly this ionic transport bottleneck.

A remarkable feature of the design is that the electrolyte is not added as a separate liquid component but arises from the cement itself. As the cement within the slab hydrated, the chemical reaction that gives concrete its strength, its pores filled with water and dissolved ions that could easily travel between the electrodes. In other words, the very process that turns printable ink into hardened concrete simultaneously creates the ionic medium the supercapacitor needs to function. This monolithic approach, in which electrode, electrolyte, and structural support are one continuous piece of material, is what the study’s title refers to in describing monolithic 3D-printed interdigitated cement-based supercapacitors for structural energy storage. It eliminates the interfaces and packaging that complicate conventional devices and means the energy-storage function can, in principle, be printed wherever a builder wants it within a larger concrete element.

Of course, an energy-storage device embedded in a building is useless if it compromises the building’s safety. Concrete in structural applications must meet strict compressive strength standards, and any multifunctional material has to prove it can carry loads without failing. The researchers therefore subjected their cement supercapacitor to mechanical testing and found that its compressive strength was comparable to that of commercial concrete used in slabs and stairs. This is the result that elevates the work from a laboratory curiosity toward practical relevance. Previous attempts at cement-based energy storage often faced a trade-off, in which adding conductive carbon or porosity weakened the material. Here, the team achieved a device that is simultaneously an electrode, an electrolyte-filled capacitor, and a structural material meeting the expectations placed on ordinary construction concrete.

The researchers also demonstrated that their devices do real electrical work. Three supercapacitors printed on the same slab and wired together successfully powered a small array of LEDs, a modest demonstration on its own but an important proof of concept showing that multiple devices fabricated from a single concrete element can be connected into a functioning energy system. Looking ahead, the team envisions these supercapacitors powering everything from emergency lighting to self-powered sensors. That second application deserves particular attention. Modern buildings increasingly depend on distributed sensor networks that monitor temperature, occupancy, air quality, and structural health, and wiring or periodically replacing batteries for thousands of such sensors is costly and cumbersome. Sensors embedded in or on concrete that draw their operating power from the concrete itself would remove that maintenance burden entirely, enabling dense, self-sustaining monitoring of the built environment.

Like any emerging technology, the cement supercapacitor has identified limits, and the team was candid about one of them. The devices operated stably under moderate heating and cooling, but at around zero degrees Fahrenheit, or minus 18 degrees Celsius, their performance started to wane. This matters because the electrolyte in the system is water-based, arising from the hydration of the cement, and water loses its ionic mobility as it approaches freezing. In cold climates, where buildings must perform year-round, a supercapacitor that fades in deep winter would be a serious limitation. The researchers state that future research will focus on fortifying the supercapacitors against cold-weather conditions, an engineering challenge that will likely involve strategies to keep the pore solution ionically active at low temperatures. It is a reminder that multifunctional materials must satisfy the demands of every function they take on, including environmental resilience across the full range of conditions a building experiences.

The broader implications reach toward what researchers call smart buildings, structures that generate, store, and manage energy within their own fabric. As Jing Zhong explains, if building materials could not only support structures but also store energy, sense their surroundings, and even interact with people, buildings would become more than passive shelters. They could become truly smart environments. The study, published in ACS Nano under the title Monolithic 3D-Printed Interdigitated Cement-Based Supercapacitors for Structural Energy Storage, was supported by funding from the Guangdong Hailong Construction Technology Company Limited, a subsidiary of China State Construction International Holdings Limited, an indication that the construction industry itself sees commercial potential in structural energy storage. Considerable work remains before supercapacitor walls appear on job sites, including scaling from small slabs to full structural elements, integrating renewable generation and power electronics, and solving the cold-weather performance gap. But the foundational demonstration is now on the table: a cement-based supercapacitor that stores energy efficiently, prints into interdigitated geometries, powers LEDs, and matches commercial concrete in compressive strength. The walls of future buildings may not merely shelter their occupants. They may quietly hold the charge that keeps those buildings alive.

Subject of Research: 3D-printed cement-based supercapacitors for structural energy storage in smart buildings

Article Title: Cement-based supercapacitors could power next-generation ‘smart’ buildings

Article References: Cement-based supercapacitors could power next-generation ‘smart’ buildings. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: cement supercapacitor, structural energy storage, 3D printing, carbon nanotubes, carbon black, concrete, smart buildings, renewable energy, energy storage, interdigitated electrodes, ACS Nano, self-powered sensors

The study, published in the journal Advanced Composites and Hybrid Materials, addresses what the authors identify as the central weakness of elastomer-based strain sensors: the interface between the conductive layer that does the electrical sensing and the elastic substrate that carries the mechanical load. The logic of this design is straightforward. Put the sensing chemistry in a thin skin on the surface, and let the thick rubber underneath handle all the stretching. But in practice, that surface layer is exactly where the device fails. When a rigid or poorly bonded coating is repeatedly deformed, cracks form at the boundary between skin and substrate, the electrical network fractures, and the signal drifts or dies. Interfacial integrity, the researchers argue, governs long-term signal stability under repeated deformation, and most conventional coating methods do not provide it.

Their solution is an ionomer-mediated interfacial-welding strategy. The substrate itself is a brominated butyl rubber that has been modified with 1-(2-hydroxyethyl)imidazole, abbreviated HBIIR. Ionomers of this kind contain ionic groups along the polymer chains; in this material, imidazolium groups associate with bromide counter-ions, forming reversible ionic cross-links that give the rubber both elasticity and internal cohesion. Crucially, the same polymer that makes up the bulk film is also dissolved into the coating mixture, where it serves as a molecular binder between the two layers.

The fabrication process reads like a lesson in polymer chemistry. A preformed HBIIR film is dip-coated in a tetrahydrofuran dispersion containing the dissolved HBIIR binder together with two conductive fillers: carbon black and whisker carbon nanotubes. As the film sits in this bath, the solvent swells its surface, loosening the polymer chains and allowing them to interdiffuse across the boundary between what will become the coating and what is already the substrate. There is no sharply defined line between layer and base; instead, chains from each side mingle freely in a swollen interphase. When the solvent then evaporates, it locks these intermingled chains into an entangled interfacial network, and the imidazolium-bromide associations that are characteristic of the ionomer re-form across the interface, adding a second, ionic source of cohesion on top of the physical entanglement.

What emerges is a conductive skin whose internal architecture is deliberately hybrid. Within the coating, the carbon black particles form dense local contacts, creating countless short-range conducting pathways, while the whisker carbon nanotubes provide longer-range connections that bridge neighboring carbon-black-rich regions. This division of labor matters for sensing performance. Carbon black junctions are highly sensitive to strain, because even tiny separations change their contact resistance dramatically, while the nanotube bridges keep the network connected at larger deformations, preventing the conductivity from collapsing when the material is stretched far. The combination is what allows a single sensor to cover both minute and massive strains without sacrificing sensitivity at either end.

The measured properties are striking. The optimized film combines an electrical conductivity of 45.1 siemens per meter with an elongation at break of 1640 percent, meaning it can be stretched to nearly seventeen times its original length before failing. As a sensor, it detects strains as low as 0.03 percent, a deformation far smaller than anything a human fingertip could feel. Its gauge factor, the ratio of relative change in electrical resistance to mechanical strain and the standard figure of merit for strain sensors, reaches a maximum of 14,016.92, an extraordinarily high value that reflects the extreme sensitivity of the carbon-black junction network at small deformations. Response and recovery times are 154 and 157 milliseconds respectively, fast enough to follow physiological motions in real time, and the device maintains reproducible signals over 10,000 deformation cycles, the durability benchmark that separates laboratory demonstrations from practical wearables.

That durability traces directly back to the welding chemistry. Because the coating and substrate share the same ionomer and their chains interpenetrate at the interface, repeated stretching does not peel the conductive skin away from the rubber beneath. The ionic cross-links add further resilience: like reversible Velcro at the molecular scale, imidazolium-bromide associations can break and re-form under stress, dissipating energy and healing local damage rather than letting cracks propagate. In conventional layered sensors, cycling typically produces progressive signal drift as the interface degrades; here, the authors report reproducible output across ten thousand cycles, suggesting the welded interface has effectively eliminated the weak point that usually limits such devices.

The applications demonstrated in the paper lean into the sensor’s clinical pedigree. Several of the authors are affiliated with the Eye Hospital and Guang’anmen Hospital of the China Academy of Chinese Medical Sciences, and the work was supported in part by funding programs tied to traditional Chinese medicine. Fittingly, one of the flagship demonstrations is pulse diagnosis. Placed on the wrist, the sensor records distinguishable radial pulse-wave signals at the three classical positions known in traditional Chinese medicine as Cun, Guan, and Chi, supporting multisite pulse monitoring of the kind practitioners have relied on for centuries. Where a physician’s fingertips must infer subtle pressure rhythms, the electronic skin converts those same mechanical waves into quantifiable resistance changes with millisecond resolution, offering a bridge between an ancient diagnostic tradition and modern instrumentation.

Beyond the wrist, the team showed that the sensor can track whole-body human motion and even serve as the control interface for a robotic hand, translating the flexion of human fingers into gesture commands that drive a mechanical counterpart. This kind of human-machine signaling is a growing area of interest for prosthetics, teleoperation, and soft robotics, and it exploits exactly the properties the welded-skin design provides: wide strain range, high sensitivity, and stable response over many cycles. Perhaps most surprising for a wearable, the sensor also exhibits an antibacterial rate of 99.9 percent against Escherichia coli and Staphylococcus aureus, a property the authors attribute to the material system itself and one that could help address the hygiene concerns that plague skin-contacting devices worn for extended periods.

The study’s authors, led by Liang Su and Chaoyang Yuan, who contributed equally, with corresponding authors Long Zheng, Jie Wu, and Yongzheng Jiao, present the work as a practical route toward sensitive, wide-range, and durable flexible strain sensors. The elegance of the approach lies in its simplicity: rather than inventing new conductive materials or exotic fabrication equipment, it uses the substrate’s own chemistry to weld a standard carbon-filled coating into place, with nothing more elaborate than a solvent bath and controlled evaporation. If the interfacial-welding principle transfers to other ionomer and filler systems, it could remove one of the most persistent failure modes in wearable sensing and bring pulse-monitoring electronic skins closer to everyday clinical and consumer use.

Subject of Research: Interface-welded conductive skins on elastomer ionomers for flexible strain sensing

Article Title: Interface-welded conductive skins on elastomer ionomers enable sensitive, wide-range strain sensing for pulse wave and human motion monitoring

Article References: Su, L., Yuan, C., Miao, S., Zhang, S., Zhou, Z., Yin, X., Zheng, L., Wu, J., & Jiao, Y. (2026). Interface-welded conductive skins on elastomer ionomers enable sensitive, wide-range strain sensing for pulse wave and human motion monitoring. Advanced Composites and Hybrid Materials. https://doi.org/10.1007/s42114-026-02081-2

Image Credits: AI Generated

DOI: 10.1007/s42114-026-02081-2

Keywords: flexible strain sensor, elastomer ionomer, interfacial welding, carbon black, carbon nanotubes, wearable technology, pulse wave monitoring, human motion sensing, gauge factor, antibacterial materials, traditional Chinese medicine, robotic hand actuation