Temperature-dependent pseudocapacitive behaviors of polyaniline-based all-solid-state fiber supercapacitors

作者：Hong, Jiao-ling; Liu, Jia-hua^*; Xiong, Xinbo; Qin, Si-yin; Xu, Xiao-ying; Meng, Xiao; Gu, Kunming; Tang, Jiaoning; Chen, Da-Zhu^*

来源：Electrochemistry Communications, 2023, 148: 107456.

DOI：10.1016/j.elecom.2023.107456

• Thermal effect
• Polyaniline
• Carbon nanotube fibers
• Fiber supercapacitors
• Pseudocapacitive behaviors

The work temperatures have a crucial influence on the performance of supercapacitors. However, temperature effects on pseudocapacitive behaviors are rarely studied for flexible high-performance fiber supercapacitors. Herein, we systematically investigated the electrochemical responses of all-solid-state fiber-based supercapacitors composed of carbon nanotube fiber (CNF) electrodes decorated with porous carbon nanotubes (CNTs)/polyaniline (PANI) and gel electrolyte at various ambient temperatures between -5 degrees C and 55 degrees C. The results show that the capacitance of the supercapacitor first enhances with the rising temperature under 40 degrees C and declines at 55 degrees C. The internal resistance presents a gradual downward trend and the self-discharge behavior accelerates at high operating temperatures. CNTs/PANI-modified flexible fiber supercapacitors are also far from unsatisfactory for cycling stability tests in a high-temperature environment. After experiencing 5000 charge-discharge cycles at 55 degrees C, the capacitance retains only 43.86 %, far below the counterpart at low temperatures. This study provides a fundamental comprehension of the temperature dependence of pseudocapacitive behaviors of PANI-based fiber supercapacitors.