Higher specific capacitance and compressibility nanocellulose based supercapacitor hydrogel electrode assembled by efficient impregnation

The rational and effective combination of different electrochemical substances to prepare high-performance supercapacitor electrodes has been widely studied by researchers. Currently, most work focuses on polymerizing conductive polymers onto the surface of nanocellulose and carbon materials, and then preparing them into supercapacitor electrodes. This method is effective, but the process is cumbersome. Therefore, we propose a simpler and more effective method. A hydrogel was prepared by using TEMPO oxidized cellulose nanofibers (TOCNF)/multi walled carbon nanotubes (MWCNT), and then immersed in aniline and FeCI3 solutions for 24 h to obtain a hydrogel electrode. At a current density of 0.5 mA cm−2, it exhibits an area specific capacitance of 1028 mF cm−2, with a maximum strain of 58 % and a compressive stress of 150 KPa. The assembled symmetrical supercapacitor exhibits a high specific capacitance of 303 mF cm−2 at a current density of 0.5 mA cm−2. The research results indicate that the proposed method is a new feasible approach for developing supercapacitors.