Controlled Fabrication of Interconnected Porous Carbon Nanosheets for Supercapacitors with a Long Cycle Life

Abstract

AbstractThe pursuit of promising precursors and simple preparation approaches boosts the development of sustainable carbon‐related energy systems. In this work, a relatively low‐cost and eco‐friendly ternary precursor system is presented for the fabrication of interconnected sheet‐structured porous carbon materials by the combination of template‐assisted pyrolysis and post‐activation. The variation of effect factors permitted the formation of tunable microstructures with multilevel pore channels, and the optimized sample (APC3‐700) with multiple desired properties (such as, large surface area, hierarchical interconnected pores, and nitrogen doping) was successfully synthesized. Due to the large electrode/electrolyte interface, short pathway for mass/charge transfer, high electrochemical activity, and low transport resistance, APC3‐700 proved to be a favorable material with high capacitance (225 F g−1 at 1 A g−1) and a high rate profile (remaining 91 % at 20 A g−1). In particular, the symmetrical supercapacitor assembled demonstrated a long cycle life with almost no capacitance decaying over 20 000 cycles. The method used may be employed for the widespread development of nanosheet‐connected carbon materials from different sources for efficient enhancement of energy storage.