Facile and low-cost fabrication of interconnected hierarchically porous carbon for high-performance supercapacitors

• Published in: Journal of alloys and compounds 2022-11, Vol.921, p.166127, Article 166127
• Main Authors: Yang, Xiaoxia, Wang, Fei, Li, Xi, Zhang, Zhuangzhuang, Wang, Chuantao, Yang, Chunming, Zhen, Yanzhong, Wang, Danjun, Fu, Feng, Chi, Ru’an
• Format: Article
• Language: English
• Subjects: Aqueous electrolytes; Capacitance; Carbon; Coal tar; Coal tar pitch; Electrochemical analysis; Electrode materials; Energy storage; Facile and low-cost; Household wastes; Interconnected hierarchically porous carbon; Low cost; Pore formation; Porous materials; Supercapacitor; Supercapacitors
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.166127

Construction of hierarchically porous carbon electrode materials is considered as an efficient strategy for improving the performance of supercapacitors. Nevertheless, how to precisely control the pore structure for preferable improvement the capacitance performance and fabricate in a cost-efficient way is still a scientific challenge. In this paper, an industrial by-product of coal tar pitch is used as precursor to prepare interconnected hierarchically porous carbons, with another domestic waste of eggshell as a pore-forming template and an inner-activator, combined with KOH in-situ activation. The as-prepared porous carbons exhibit large specific surface area (SBET, 1398–2103 cm2 g−1), well-developed interconnected hierarchically architecture, and excellent electrochemical performance. Among them, the optimal TS-PCE-4 based symmetric supercapacitor possesses a high capacitance of 238 F g−1 at 0.5 A g−1 with an excellent rate capability, exhibits long cycle stability with capacitance retention of 95.85 % after 10,000 cycles, and delivers energy densities of 8.27–5.47 Wh kg−1 at power density in the range of 125–4925 W kg−1 in 6 M KOH aqueous electrolyte. This work offers a facile and low-cost route to construct interconnected hierarchically porous carbons for energy storage devices. [Display omitted] •An industrial by-product of coal tar pitch was used to fabricate the hierarchically porous carbons via a facile route.•The domestic waste of eggshell was served as a pore-forming template and an inner-activator.•The carbons show large specific surface area and well-developed interconnected hierarchically porous architecture.•The optimum sample displays outstanding supercapacitor performance.