In the quest for advanced materials capable of revolutionizing energy storage and thermal management systems, nano-phase change emulsions (NPCEs) have emerged as a front-runner due to their remarkable combination of high energy density and exceptional heat transfer efficiency. However, the practical application of NPCEs, particularly under low-temperature and shear-intensive conditions, has been severely hindered by issues related to droplet coalescence, supercooling, and general instability. These phenomena compromise the emulsions’ capacity to maintain consistent performance, threatening their potential deployment in critical areas such as cold-chain logistics and sustainable energy storage systems. A groundbreaking study published recently in the journal Industrial Chemistry & Materials introduces a novel ultrasonic regeneration methodology that promises to overturn these long-standing barriers, heralding a new era for NPCE application in temperature-sensitive environments.
The intrinsic challenge with NPCEs lies in their susceptibility to supercooling—a deviation from equilibrium behavior where the emulsion remains in a liquid state well below its melting point—and mechanical degradation induced by shear stresses prevalent in operational systems. Such instabilities precipitate phase separation and droplet aggregation, thus steadily undermining the thermal efficiency of the emulsions over time. Traditionally, once destabilization begins, restoring the emulsion’s functional integrity would necessitate halting the system, an impracticable adjustment in many real-world applications. Scientists at South China University of Technology, spearheaded by Professor Zhengguo Zhang, have pioneered a regeneration strategy employing high-energy ultrasound that actively restores NPCE performance in real time. This continuity in operation not only preserves thermal management capabilities but also vastly extends the practical lifespan of emulsions in challenging environments.
The core innovation revolves around the application of ultrasonic waves at carefully calibrated energy levels that disrupt and re-condense coalesced droplets without necessitating system downtime. This sonic energy imparts sufficient localized agitation, effectively reversing droplet merging and re-establishing the finely dispersed emulsion microstructure crucial for optimal heat exchange. Crucially, the process manages to avoid disturbing the emulsion’s inherent phase change dynamics, maintaining the delicate balance necessary for latent heat storage and release. This breakthrough addresses the heretofore unresolved problem of low-temperature shear degradation by enabling on-the-fly recovery, ensuring that NPCEs can reliably function under continuous operational stress.
Central to enhancing NPCE stability was the team’s rigorous optimization of nucleating agents—substances that catalyze crystallization within the emulsion. By meticulously selecting and tuning these agents at the nanoscale, researchers nearly eliminated supercooling effects, achieving a phase transition that closely aligns with theoretical melting points. This precision control over nucleation dynamics mitigates the common lag in crystallization, preventing extended liquid states that compromise energy storage and transfer. Moreover, the investigation extended to elucidate the microscopic interactions and physicochemical principles governing shear-induced destabilization, offering foundational insights critical to engineering more resilient emulsions.
The significance of this development cannot be overstated, especially in the context of cold-chain applications where temperature consistency is paramount for preserving perishables and pharmaceuticals. NPCEs enhanced through ultrasonic regeneration promise a transformative impact by offering reliable, continuous thermal buffering that overcomes the limitations imposed by environmental fluctuations and mechanical stresses. The approach also aligns with broader energy sustainability goals, providing a scalable solution for thermal energy storage systems that demand consistent performance over extended cycles and across diverse temperature ranges.
The research team demonstrated that the ultrasonic regeneration process seamlessly integrates with existing thermal cycles, enabling continuous heat exchange without the need for operational interruptions. This facet is particularly critical for industrial adoption, where minimizing downtime translates directly into economic efficiency. By embedding ultrasonic regeneration within the emulsification system, the approach effectively converts a traditionally static material limitation into a dynamic feature, capable of adapting in real time to fluctuating mechanical and thermal stresses.
From a materials science standpoint, this work exemplifies the synergy between nanotechnology, acoustics, and thermodynamics to solve a complex engineering challenge. The interplay of carefully engineered nucleating agents with ultrasonic energy creates a feedback loop that sustains emulsion microstructure and phase-change properties simultaneously. The methodology not only revitalizes the droplets that have begun to coalesce but also sustains supercooling suppression through controlled crystallization kinetics, a dual mechanism essential for long-term stability.
Looking forward, the research team envisions scaling this ultrasonic regeneration technology for industrial-scale implementations, targeting sectors where thermal storage and cold storage are critical. Efforts are underway to refine regeneration efficiency and reduce energy consumption associated with ultrasonic application, potentially extending the technology’s footprint to other domains requiring precise thermal management under dynamic conditions. Such advancements could spark a ripple effect across energy infrastructure, pharmaceuticals, food preservation, and even aerospace thermal regulation.
Crucially, the study dispels the pervasive notion that phase change emulsions are inherently fragile under mechanical and thermal stress, revealing instead a robust pathway to sustained stability and performance. This paradigm shift opens new avenues for research and development, highlighting the importance of integrating physical stimulus-responsive processes within material systems to extend functionality beyond native constraints. The multi-disciplinary approach embodied by this research sets a benchmark for future innovations in complex fluids and energy materials.
By bridging the gap between laboratory innovation and practical application, the South China University team exemplifies how targeted scientific breakthroughs can respond to industrial challenges. Their approach combines fundamental understanding with technical ingenuity, setting a precedent for how similarly complex material challenges might be tackled through real-time adaptive regeneration processes. This heralds a future where thermal energy storage media are not just passive materials but responsive systems capable of self-healing and performance optimization.
This breakthrough resonates strongly within the broader context of global efforts to optimize low-carbon technologies and sustainable energy systems. The efficient use of phase change materials, rendered viable through ultrasonic regeneration, stands poised to accelerate the integration of renewable energy sources, reduce energy waste, and enhance the reliability of temperature-sensitive supply chains. Such progress underscores the vital role of innovative materials research as a cornerstone of the energy transition and modern industrial sustainability.
The research team behind this transformative work includes Yuyao Guo, Jinxin Feng, Zhihao Xia, Ziye Ling, Xiaoming Fang, and Zhengguo Zhang, all from South China University of Technology. Their work was supported by the Dongguan Key Research & Development Program, reflecting significant institutional investment in pioneering thermal materials research. As the field evolves, their contributions will likely inspire further iterations of ultrasonic regeneration techniques and novel formulations of nano-phase change emulsions, cementing the practical viability of these materials in the decades to come.
Subject of Research: Not applicable
Article Title: Ultrasonically regenerable nano-phase change emulsions with low supercooling and high shear stability
News Publication Date: 28-Jul-2025
Web References:
Industrial Chemistry & Materials Journal
DOI Link
Image Credits: Ziye Ling and Zhengguo Zhang, South China University of Technology, China
Keywords
nano-phase change emulsions, supercooling, ultrasonic regeneration, shear stability, thermal energy storage, nucleating agents, cold-chain logistics, phase change materials, latent heat storage, emulsion stability, energy-efficient heat transfer, thermal management
