Liang Xiaohong, Liu Guangming
Department of Chemical Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230026, P. R. China.
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, P. R. China.
ACS Appl Mater Interfaces. 2024 Oct 23;16(42):56997-57003. doi: 10.1021/acsami.4c10344. Epub 2024 Oct 14.
Aqueous poly(vinyl alcohol) (PVA) gel electrolyte-based quasi-solid-state electrical double-layer capacitors (QSEDLCs) have been extensively investigated in the past ten years, but challenges remain to fabricate the PVA gel electrolyte possessing both superior mechanical and outstanding electrochemical performances. Herein, we develop a strategy to address this issue by a rational design of PVA gel electrolytes, based on a combination of the freeze-thaw (FT) method and sodium perchlorate (NaClO)-based water-in-salt (WIS) electrolyte. Our study demonstrates that either the FT method or the NaClO-based WIS electrolyte can improve both the mechanical performance of the PVA gel electrolyte by increasing the crystallization of PVA chains and the electrochemical performance of the PVA gel electrolyte-based QSEDLC by different mechanisms. In comparison with the conventional solvent evaporation method, this work provides an effective strategy to concurrently improve both the mechanical and electrochemical performances of aqueous QSEDLCs.
在过去十年中，基于水相聚乙烯醇（PVA）凝胶电解质的准固态双电层电容器（QSEDLCs）得到了广泛研究，但要制备出兼具优异机械性能和出色电化学性能的PVA凝胶电解质仍面临挑战。在此，我们基于冻融（FT）法和高氯酸钠（NaClO）基盐包水电解质（WIS）相结合的方式，通过对PVA凝胶电解质进行合理设计，开发出一种解决该问题的策略。我们的研究表明，FT法或基于NaClO的WIS电解质均可通过不同机制提高PVA链的结晶度来改善PVA凝胶电解质的机械性能，并提升基于PVA凝胶电解质的QSEDLC的电化学性能。与传统的溶剂蒸发法相比，这项工作为同时提高水相QSEDLC的机械性能和电化学性能提供了一种有效策略。
