Tianjin, China – Researchers from the School of Chemical Engineering and Materials at Tianjin University of Science and Technology (TUST) have achieved a significant breakthrough in the field of hydrogel electrolytes. The team from the Polymer Material Modification and Processing Group has made important progress in regulating the zinc ion desolvation process through a chain-chain synergistic hydrogel electrolyte mechanism.

The related research findings, entitled "Chain-Chain Synergistic Hydrogel Electrolytes Regulate Zinc Ions Desolvation for Stabilized Anodes and High Operating Voltage in Flexible Zinc Ions Hybrid Capacitors," have been published in the prestigious international journal Angewandte Chemie International Edition. TUST is listed as the first author and corresponding author institution. Dr. Zhang Hang, a young faculty member from the School of Chemical Engineering and Materials, and Wan Li, a 2024 master's graduate, are co-first authors of the paper. The corresponding authors are Dr. Zhang Hang from TUST, Associate Professor Cui Yongyan from TUST, and Associate Researcher Lei Da from the Qinghai Institute of Salt Lakes, Chinese Academy of Sciences.

To maximize energy density output, the complementary charge storage mechanism of aqueous zinc-ion hybrid capacitors (ZIHCs) demonstrates superiority and advancement. However, persistent water-induced side reactions and uncontrollable dendrite growth on zinc anodes remain critical challenges. Furthermore, interface optimization between hydrogel electrolytes and electrodes is essential for the stability and kinetic reversibility of flexible zinc-based energy storage devices. Based on a chain-chain synergistic regulation mechanism, this research designed a P(AM-SBMA)/gelatin hydrogel electrolyte (PSG) with a special semi-interpenetrating network structure, aiming to regulate the zinc ion desolvation process, thereby optimizing the operating voltage of flexible ZIHCs and stabilizing the surface chemistry of the zinc anode.

The developed PSG-5 hydrogel electrolyte broadens the electrochemical stability window of flexible ZIHCs to 2.45 V and achieves a high Zn²⁺ transference number of 0.87, along with highly reversible zinc anode deposition/stripping behavior. Moreover, the corresponding flexible ZIHC exhibits an operating voltage as high as 2.2 V and delivers an excellent energy density of 117 Wh kg⁻¹ at a power density of 293 W kg⁻¹ . By preparing a hydrogel electrolyte capable of stabilizing the zinc anode and widening the electrochemical stability window, this work provides valuable insights for developing high-efficiency flexible ZIHCs.

In recent years, guided by the "Pioneer Plan," the School of Chemical Engineering and Materials has implemented the "Huacai Young Faculty Development Program" to support young faculty in their scientific research and foster their professional growth. Several young faculty members have already published research results in authoritative journals within their fields as first authors. Moving forward, the School will continue to optimize its support mechanisms, providing broader development opportunities for young faculty and promoting the output of more original and groundbreaking achievements, thereby contributing to the university's goal of becoming a high-level research-oriented institution.

Link to the original article:
https://doi.org/10.1002/anie.202507403