Hua Mutian, Wu Shuwang, Jin Yin, Zhao Yusen, Yao Bowen, He Ximin
Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
Adv Mater. 2021 Jul;33(26):e2100983. doi: 10.1002/adma.202100983. Epub 2021 May 31.
All-solid-state supercapacitors are seeing emerging applications in flexible and stretchable electronics. Supercapacitors with high capacitance, high power density, simple form factor, and good mechanical robustness are highly desired, which demands electrode materials with high surface area, high mass loading, good conductivity, larger thickness, low tortuosity, and high toughness. However, it has been challenging to simultaneously realize them in a single material. By compositing a superficial layer of tough hydrogel on conductive and low tortuous foams, a thick capacitor electrode with large capacitance (5.25 F cm ), high power density (41.28 mW cm ), and good mechanical robustness (ε = 140%, Γ = 1000 J m ) is achieved. The tough hydrogel serves as both a load-bearing layer to maintain structural integrity during deformation and a permeable binder to allow interaction between the conductive electrode and electrolyte. It is shown that the tough hydrogel reinforcement is beneficial for both electrical and mechanical stability. With a simple design and facile fabrication, this strategy is generalizable for various conductive materials.
全固态超级电容器在柔性和可拉伸电子器件中有着新兴的应用。人们迫切需要具有高电容、高功率密度、简单外形和良好机械鲁棒性的超级电容器，这就要求电极材料具有高表面积、高负载量、良好的导电性、较大的厚度、低曲折度和高韧性。然而，要在单一材料中同时实现这些特性一直具有挑战性。通过在导电且低曲折度的泡沫上复合一层坚韧的水凝胶表层，获得了一种具有大电容（5.25 F cm ）、高功率密度（41.28 mW cm ）和良好机械鲁棒性（ε = 140%，Γ = 1000 J m ）的厚电容器电极。坚韧的水凝胶既作为承重层在变形过程中维持结构完整性，又作为可渗透的粘合剂使导电电极与电解质之间能够相互作用。结果表明，坚韧的水凝胶增强对于电气和机械稳定性都有益。通过简单的设计和简便的制造，这种策略可推广到各种导电材料。
