Co/P co-doped bamboo-based woodceramics with a sandwich structure modified by carbon nanotube electrodeposition as supercapacitor electrodes.

ABSTRACT

Exploring new electrode structures and co-doped composite biomass material electrodes is considered to be an effective way of developing cheap, efficient carbon-based supercapacitors. A bamboo-based sandwich-structured matrix was prepared from thin bamboo veneer and bamboo fiber by pretreatment with H3PO4 and Co2+-catalyzed graphitization. The pore structure was modulated by hydrothermal activation with NaOH and electrodeposition of carbon nanotubes (CNTs) to obtain CNTs modified, Co/P co-doped sandwich-structured woodceramics electrode (CNT@Co/P). It not only has an obvious sandwich structure, but also retains the natural structural characteristics of bamboo. The specific capacitance of the resulting electrode (CNT@Co/P-20) is as high as 453.72F/g using 1 wt% of carboxylated multi-walled carbon nanotubes (CMWCNT) solution as the deposition electrolyte at a current density of 0.2 A/g for 20 min at room temperature. When the power density is 500 W/kg, the energy density reaches 21.3Wh /kg, showing a good electrochemical performance.