Regulating the properties of activated carbon for supercapacitors: impact of particle size and degree of aromatization of hydrochar

Advanced Composites and Hybrid Materials 2023

Regulating the properties of activated carbon for supercapacitors: impact of particle size and degree of aromatization of hydrochar.

Jian Peng   · Xiheng Kang   · Siyu Zhao   · Yongjun Yin · Peitao Zhao   · Arthur J. Ragauskas· Chuanling Si   · Xueping Song

摘要：Hydrochar (HC), obtained by the hydrothermal carbonization (HTC) of biomass, is an excellent precursor for preparing activated carbon (AC). However, the efects of the intrinsic properties of HC on the microstructure and electrochemical properties of AC are largely unknown. This study investigates the impact of particle size and the degree of aromatization of in-situ HC on the microstructure and electrochemical properties of AC. Our results show that a large particle size and a high degree of aromatization help protect the HC from overactivation by ZnCl2, resulting in an large specifc surface area (SSA > 2000 m2 /g) and high mesopore to micropore volume ratio value ( Vmes/Vmic > 0.3) of the AC. Electrochemical performance measurements show a maximum specifc capacitance of 218 F/g at 0.5 A/g was achieved in all samples where the AC (AC180-10 h) was prepared by activating HC180-10 h with a large size, a high degree of aromatization, and abundant surface oxygen-containing functional groups. After AC180-10 h was assembled into a supercapacitor, the specifc capacitance of AC180-10 h still reached 158 F/g at 0.5 A/g, and it showed excellent cycling stability. This study advances the understanding of the impact of HC particle size and degree of aromatization on AC properties, providing new insights into tailoring HC qualities so that improving improve the properties of AC.

DOI：https://doi.org/10.1007/s42114-023-00682-9