Wang Qi, Liu Pengyuan, Zhou Fanyu, Gao Lei, Sun Dandan, Meng Yuhang, Wang Xuebin
National Laboratory of Solid State Microstructures (NLSSM), Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China.
Molecules. 2022 Feb 12;27(4):1239. doi: 10.3390/molecules27041239.
Low-grade heat energy recycling is the key technology of waste-heat utilization, which needs to be improved. Here, we use a zinc-assisted solid-state pyrolysis route to prepare zinc-guided 3D graphene (ZnG), a 3D porous graphene with the interconnected structure. The obtained ZnG, with a high specific surface area of 1817 m·g and abundant micropores and mesopores, gives a specific capacitance of 139 F·g in a neutral electrolyte when used as electrode material for supercapacitors. At a high current density of 8 A·g, the capacitance retention is 93% after 10,000 cycles. When ZnG is used for thermally chargeable supercapacitors, the thermoelectric conversion of the low-grade heat energy is successfully realized. This work thus provides a demonstration for low-grade heat energy conversion.
低品位热能回收是余热利用的关键技术，仍有待改进。在此，我们采用锌辅助固态热解路线制备了锌导向三维石墨烯（ZnG），这是一种具有相互连接结构的三维多孔石墨烯。所制备的ZnG具有1817 m²·g的高比表面积以及丰富的微孔和介孔，用作超级电容器的电极材料时，在中性电解质中的比电容为139 F·g。在8 A·g的高电流密度下，经过10000次循环后电容保持率为93%。当ZnG用于热充电超级电容器时，成功实现了低品位热能的热电转换。因此，这项工作为低品位热能转换提供了一个范例。
