Preparation of cellulose-derived biomass porous carbon and its supercapacitor performance

Using cotton cellulose as raw material, the hierarchical porous carbon (HPC) samples were prepared by pyrolyzing the mixture of magnesium nitrate, urea and cellulose. The specific surface area and pore structure of porous carbon were regulated by changing the calcination temperature and KOH activation treatment. By comparing the cyclic voltammetry curve, galvanostatic charge-discharge curve, specific capacity and other electrochemical parameters of the activated samples which were pre-calcined at three different temperatures, the results showed that 4AC@HPC800 sample had excellent electrochemical performance as the working electrode of supercapacitor, and its specific surface area reached 2433.8 m2·g-1. The specific capacitance was as high as 234.7 F·g-1 at the current density of 1 A·g-1, and 207.6 F·g-1 at the high current density of 10 A·g-1, indicating that it had good rate performance. The electrode still presented a capacity of 196.1 F·g-1 after 10000 cycles at the current density of 2 A·g-1, indicating that it can work for a long time. © 2022 Chemical Industry Press. All rights reserved.