Abstract:
Using waste disposable bamboo chopsticks as carbon source, bamboo-based porous carbon was prepared by direct pyrolysis followed by washing with deionized water after pretreatment with NaOH and Na
2SO
3. The surface morphology, specific surface area, pore structure and surface wettability were characterized and analyzed. The results showed that compared with bamboo-based porous carbon(PC-H) pretreated with deionized water, bamboo-based porous carbon(PC-Na) pretreated with NaOH and Na
2SO
3 mixture possessed high surface area(1 434 m
2/g), well-developed porous structure(0.69 cm
3/g) and excellent wettability(water contact angle of about 53.5°). Using the produced bamboo-based porous carbon as the positive electrode, the assembled aqueous Zn-ion hybrid supercapacitor(ZIHSC) displayed a high specific capacity of 75.6(mA·h)/g at a current density of 0.2 A/g. When the current density increased to 50 times, the specific capacitance retention rate was 52%, showing excellent rate performance. The maximum energy density was 59.3(W·h)/kg and the maximum power density was up to 7.6 kW/kg. The specific capacitance decays was only 2.7% after 5 000 charge-discharge cycles at a current density of 5 A/g, showing excellent cycle stability.