In a transformative departure from conventional approaches, an innovative interdisciplinary study harnesses principles from catalytic chemistry—namely the d-band center modulation strategy—to re-engineer the zinc electrode interface. This novel concept pivots on electronic structure manipulation, precisely altering the reaction kinetics governing zinc surface interactions. By introducing a carefully selected organic additive, the study achieves fine control over the electrode surface electronic properties, effectively suppressing side reactions at their source. This breakthrough marks a paradigm shift, moving beyond symptomatic treatments to fundamental kinetic regulation, significantly enhancing the cyclical longevity and operational safety of aqueous zinc batteries.

Catalytic science has long recognized the d-band center position as a critical descriptor of surface reactivity; it dictates the adsorption strength of reactant intermediates on metallic catalysts, thereby modulating reaction pathways and rates. Translating this concept to battery science, the authors identify the HER occurring on the zinc anode surface as an electrocatalytic event. This insight prompted the hypothesis that shifting the d-band center of surface zinc atoms could weaken the adsorption of hydrogen intermediates (H*), which are crucial to the HER mechanism. By effectively “applying the brakes” to these intermediates’ adsorption, the rate of hydrogen evolution can be suppressed, addressing a core challenge that has hampered the practical realization of durable aqueous zinc metal anodes.

To operationalize this concept, the research team screened a variety of organic molecules, ultimately pinpointing oxalic acid (OA) as an exemplary interface modulator. Leveraging first-principles computational methods, they demonstrated that OA molecules specifically adsorb onto zinc surfaces not merely by physical coverage but through inducing significant shifts in the zinc electronic structure. Quantitatively, the d-band center of surface zinc atoms shifts downward from -6.896 eV to -7.062 eV upon OA adsorption. This downward shift correlates with a decreased capability of zinc electrons to adsorb hydrogen intermediates, thus reducing both the thermodynamic drive and kinetic facilitation of HER. Computational adsorption energy simulations further corroborated this mechanism, illustrating how OA-modulated zinc surfaces favor hydrogen desorption, thereby impeding deleterious side reactions at a fundamental electronic level.

Beyond surface electronic modulation, this research sheds light on an equally critical effect of oxalic acid within the battery electrolyte’s bulk solution. Using a multidisciplinary toolkit—including Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and molecular dynamics simulations—the team revealed that OA molecules interact strongly with zinc ions in solution, partially replacing water molecules within the primary solvation sheath around Zn²⁺. This modification has two key consequences: the first is a decreased coordination of water molecules directly to zinc ions, reducing their availability to participate in parasitic side reactions. The second involves weakening sulfate anion–zinc ion interactions, which in turn prevents the interfacial accumulation of insulating zinc hydroxide sulfate by-products. Together, these effects produce a synergistic “solvation editing,” complementing the surface electronic modulations to yield a stable and clean interphase conducive to uniform zinc plating and stripping.

The dual-functionality of oxalic acid—both as an electronic structure modulator at the electrode surface and a solvation structure editor in the electrolyte—represents a multifunctional strategy to synergistically suppress multiple degradation pathways in aqueous zinc batteries. This two-pronged approach stabilizes the electrodeposition environment, reducing dendrite nucleation and growth, curbing corrosive side reactions, and minimizing the formation of electrically insulating by-products. The resultant interface displays significantly improved chemical and mechanical stability, fostering homogeneous zinc dissolution and deposition that prolongs battery cycle life and operational safety.

Translating this molecular and interface design strategy into practical performance gains, the researchers conducted extensive electrochemical evaluations. Zinc-iodine (Zn||I₂) full cells incorporating the oxalic acid additive demonstrated remarkable cycle stability, maintaining 92.8% of their initial capacity even after 10,000 charge-discharge cycles—an unprecedented endurance metric for aqueous zinc metal batteries. Furthermore, the team showcased the scalability and robustness of their approach by assembling ampere-hour-scale pouch cells, which sustained stable electrochemical performance under mechanical deformation, such as bending. These demonstrations highlight the approach’s feasibility for real-world applications requiring flexible, safe, and long-lasting energy storage devices.

Reflecting on their innovative cross-disciplinary methodology, the authors emphasize the power of integrating catalytic theory insights to resolve vexing challenges in battery science. They state, “This work is a successful exploration of interdisciplinary cross-fertilization. It enlightens us that solving stubborn problems in the energy storage field sometimes requires drawing wisdom from adjacent disciplines. Catalysis theory provides us with a new lens through which to understand and design electrode/electrolyte interfaces.” Their success portends the broader potential of leveraging fundamental principles from heterogeneous catalysis and surface chemistry to design next-generation metal anode architectures.

Significantly, the strategy pioneered here transcends aqueous zinc systems. By demonstrating effective modulation of electrode surface electronic structures to regulate reaction kinetics, this approach lays groundwork for tackling interfacial challenges in other reactive metal anodes, including lithium, sodium, and aluminum. Each of these chemistries shares analogous issues with dendrite formation, hydrogen evolution (or equivalent side reactions), and interfacial instability. Thus, the catalysis-inspired paradigm offers a versatile toolkit for engineering safer, high-performance battery systems critical for future sustainable energy storage solutions.

This study represents a landmark advance in aqueous zinc battery technology, achieving low-cost and facile additive-based interfacial engineering that delivers exceptional electrochemical stability, safety, and practical applicability. More importantly, it exemplifies a new horizon for electrode design guided by precise electronic structure control, rather than purely empirical formulations. As global demands for durable, safe, and sustainable energy storage grow increasingly urgent, such pioneering interdisciplinary research that bridges theory to application will be a defining driver of future energy technology revolutions.

Subject of Research: Energy Storage, Aqueous Zinc-ion Batteries, Electrode Interface Engineering
Article Title: Catalysis-Inspired Electronic Structure Modulation Enables Durable and Safe Aqueous Zinc Metal Anodes
Web References: 10.1016/j.scib.2026.01.033
Image Credits: ©Science China Press

Keywords

Aqueous Zinc-Ion Battery, Zinc Metal Anode, Hydrogen Evolution Reaction, D-Band Center Modulation, Oxalic Acid Additive, Electrode Interface, Solvation Structure, Hydrogen Adsorption, Electrocatalysis, Cycle Stability, Energy Storage, Dendrite Suppression

A groundbreaking stride in this domain has been achieved through the development of deep eutectic aqueous-organic electrolytes that strategically disrupt the hydrogen-bonding network of water molecules. By doing so, these novel electrolytes simultaneously enhance the reversibility of MnO_2 at the cathode and enable stable cycling of the zinc anode without initiating water decomposition, a traditional source of efficiency loss. This delicate balance is critical not only to extend the battery lifecycle but also to maintain high Coulombic efficiencies over thousands of cycles, a benchmark for commercial viability.

The innovative electrolytes bring a non-flammable character to the system, greatly improving safety parameters—a crucial factor for grid-scale storage where large quantities of energy are stored. By regulating the solvation structure of Zn^2+ cations and controlling the phase of deposited MnO_2, these eutectic solutions engineer the morphology of the cathode’s active material. This results in the formation of layered MnO_2 structures with facilitated ion-transport pathways that enhance the stripping efficiency, helping to unlock higher performance levels that were previously unattainable with aqueous electrolytes.

Notably, these electrolytes also elevate the oxygen evolution overpotential to levels significantly higher than the MnO_2 deposition potential, a breakthrough that completely suppresses the unwanted side reaction of oxygen evolution. This suppression is vital, as oxygen evolution is not only a wasteful process but can also produce gas bubbles that degrade electrode integrity and battery endurance. This mechanism underscores a novel electrochemical environment where the intrinsic stability of the battery components is decisively enhanced.

The local interfacial environment at the cathode is another arena where these deep eutectic electrolytes bring transformative changes. They create localized pH gradients at the electrode interface, a nuanced effect that critically impacts essential processes such as proton transport and MnO_2 stripping. This local pH modulation optimizes the cathode reactions in a manner that fosters more efficient and reversible electrochemical behavior, thereby driving the overall battery performance upwards.

This holistic approach addresses multiple interrelated challenges simultaneously—corrosion, electrolyte instability, parasitic gas evolution, and poor reversibility—thus marking a significant departure from piecemeal solutions previously explored. By focusing on intimate molecular-level interactions within the electrolyte, researchers have concretized a practical path toward achieving long cycle lives (>5,000 cycles) without the need for external acid additives, which have traditionally been used to maintain acidic conditions but at the cost of zinc metal corrosion.

The enhancement in Coulombic efficiency maintained over prolonged cycling not only cements the practicality of this system but also signifies a leap towards higher energy density zinc–manganese batteries. These advancements have profound implications for stationary energy storage applications that demand both safety and sustainability alongside performance. The strategy of rational electrolyte design emerging from this research pushes the frontier of aqueous battery technologies closer to their theoretical potential.

Behind these accomplishments lies a detailed understanding of zinc’s electrochemical behavior in complex electrolyte environments. Traditionally, zinc anodes suffer from dendritic growth and corrosion-induced shape changes that detract from cycling stability. In this eutectic medium, zinc’s solvation environment is modulated, promoting more uniform deposition and dissolution, which underpins the remarkable endurance demonstrated by these batteries. This design principle reflects a nuanced grasp of solvation dynamics and electrode interfacial science.

For the cathode, the phase and morphology control bestowed by the deep eutectic electrolytes directly impact the MnO_2 layer’s crystallinity and ionic pathways. This layer is neither too compact nor irregular, allowing faster ion transport and minimizing kinetic barriers associated with MnO_2 redox reactions. Such structural tuning is essential for unlocking higher capacities and operational voltages, both of which are critical to making zinc–manganese batteries commercially attractive.

The elimination of parasitic gas evolution, chiefly oxygen and hydrogen, has been a persistent challenge for aqueous battery chemistries. These side reactions not only squander energy but also present safety hazards due to pressure build-up and electrode damage. Raising the oxygen evolution overpotential well above the deposition potential acts as a gatekeeper, essentially preventing the onset of this undesirable reaction during cycling. This breakthrough offers a clearer path toward aqueous battery systems that can rival their non-aqueous counterparts.

Equally important is the ability of this electrolyte system to maintain a benign pH environment locally while facilitating proton transport for the MnO_2/Mn^2+ conversion. This balance mitigates acid-driven corrosion at the zinc side while simultaneously optimizing cathode kinetics, an intersection that had proven elusive until now. The creation of localized interfacial pH gradients represents an elegant self-regulating mechanism within the battery, enhancing both safety and efficiency.

The implications of this research stretch beyond zinc–manganese batteries alone. The concept of disrupting hydrogen bonding networks to design electrolytes with tailored solvation properties opens pathways for other aqueous battery chemistries hindered by water’s reactivity. Additionally, the extensive cycle life without acid additives indicates potential for reduced maintenance and greater system durability, attributes vital for grid-storage economics.

Moreover, these eutectic electrolytes’ non-flammable attributes catapult the battery technology into safer operations, a non-trivial advantage for stationary applications often located near populated areas. This safety profile, combined with high energy density and long-term stability, may attract widespread industry and governmental interest, catalyzing a shift in how sustainable energy infrastructures are designed.

The global approach employed in this research exemplifies the power of interdisciplinary collaboration, blending electrochemistry, materials science, and molecular engineering to realize a practical solution. Such integrative methodologies underscore the future of battery innovation, where holistic understanding catalyzes technological leaps rather than incremental improvements.

As this new generation of zinc–manganese batteries moves from the laboratory toward commercial applications, questions remain regarding scalability and cost-effectiveness of these novel eutectic electrolyte formulations. However, the foundational proof-of-concept demonstrated promises a compelling avenue for further exploration and optimization by both academic and industrial research communities.

In summary, these aqueous eutectic electrolytes stand to redefine the landscape of zinc–manganese energy storage by resolving long-standing bottlenecks of corrosion, electrolyte instability, and parasitic reactions. This breakthrough augurs well for high-energy, safe, and durable batteries necessary for the energy transition and the integration of renewable sources—marking a pivotal advancement in the quest for sustainable power solutions.

Subject of Research: Electrolyte engineering in aqueous Zn^2+/Zn||MnO_2/Mn^2+ batteries to achieve stable, high-performance, and long-cycle-life energy storage without acid-induced corrosion and parasitic gas evolution.

Article Title: Aqueous eutectic electrolytes suppress oxygen and hydrogen evolution for long-life Zn||MnO_2 dual-electrode-free batteries.

Article References:
Li, J., Li, C., Liu, B. et al. Aqueous eutectic electrolytes suppress oxygen and hydrogen evolution for long-life Zn||MnO_2 dual-electrode-free batteries. Nat Energy (2026). https://doi.org/10.1038/s41560-025-01958-8

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41560-025-01958-8