Zaidi Syed Farrukh Alam, Saeed Aiman, Ho Van-Chuong, Heo Jun Hyuk, Cho Hui Hun, Sarwar Nasir, Lee Nae-Eung, Mun Junyoung, Lee Jung Heon
School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea; Department of Metallurgical and Materials Engineering, University of Engineering and Technology (UET), Lahore 39161, Pakistan.
Department of Biomedical Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Int J Biol Macromol. 2023 Apr 15;234:123725. doi: 10.1016/j.ijbiomac.2023.123725. Epub 2023 Feb 21.
Hydrogel-based electrolytes for flexible solid-state supercapacitors (SSCs) have received significant attention due to their mechanical robustness and stable electrochemical performance over a wide temperature range. However, achieving flame retardancy in such SSCs at subzero temperatures to increase their practical utility remains challenging. Furthermore, there is a need for sustainable and bio-friendly SSCs that use natural polymer-based hydrogel electrolytes. This study reports a novel approach for developing a chitosan-reinforced anti-freezing ionic conductive gelatin hydrogel to meet these demands. Immersion of chitosan-containing gelatin hydrogels in salt solutions caused chitosan precipitation, resulting in composite hydrogels. The precipitated chitosan contributes to the reinforcement of the gelatin hydrogel network, resulting in a high mechanical toughness of up to 3.81 MJ/m, a fracture energy of 26 kJ/m, anti-freezing properties (below -30 °C), and excellent flame retardancy without softening. Furthermore, the hydrogel exhibits excellent electrochemical performance, with an ionic conductivity ranging from 72 mS/cm at room temperature (26 °C) to 39 mS/cm at -30 °C. The proposed hydrogel exhibits potential for use in SSC as a gel polymer electrolyte. This study demonstrates a novel strategy for controlling the mechanical, thermal, and electrochemical characteristics of flexible supercapacitors using biological macromolecules.
用于柔性固态超级电容器（SSC）的水凝胶基电解质因其机械强度高以及在很宽温度范围内具有稳定的电化学性能而受到广泛关注。然而，要在零下温度下使此类SSC具备阻燃性以提高其实用性仍具有挑战性。此外，还需要使用基于天然聚合物的水凝胶电解质的可持续且生物友好型SSC。本研究报告了一种开发壳聚糖增强的抗冻离子导电明胶水凝胶的新方法，以满足这些需求。将含壳聚糖的明胶水凝胶浸入盐溶液中会导致壳聚糖沉淀，从而形成复合水凝胶。沉淀的壳聚糖有助于增强明胶水凝胶网络，从而产生高达3.81 MJ/m的高机械韧性、26 kJ/m的断裂能、抗冻性能（低于-30°C）以及优异的阻燃性且不会软化。此外，该水凝胶具有出色的电化学性能，离子电导率在室温（26°C）下为72 mS/cm，在-30°C下为39 mS/cm。所提出的水凝胶作为凝胶聚合物电解质在SSC中具有应用潜力。本研究展示了一种使用生物大分子来控制柔性超级电容器的机械、热和电化学特性的新策略。
