High-performance lithium-ion capacitor based on N, S co-doped porous foam carbon derived from bamboo

Abstract

Based on long cyclic life and high power/energy density, the lithium-ion capacitor (LIC) has a growing trend towards applications on the energy reserve side. Nevertheless, the imbalance of storage capacity and reaction kinetic between cathode and anode is a major obstacle to achieving high-performance LIC. Herein, N, S co-doped porous foam carbon derived from bamboo (BLZSC) is prepared via a template method coupled with chemical activation. BLZSC as the cathode presents a high-specific surface area (SSA) of 2288.03 m2 g−1 and a superior capacitive capability. Furthermore, nano-ZnS/porous carbon derived from bamboo (CZS) is prepared via a simple sulfuration method, which is made up of nano-ZnS uniformly distributed on a carbon framework. CZS as the anode shows a fine rate performance, and the capacitive-dominated mechanism in the electrochemical reaction contributes to achieving the behavior of fast charge-discharge. The CZS anode and BLZSC cathode are employed to assemble the LIC. What's more, the CZS//BLZSC LIC can achieve a high energy density of 158 Wh kg−1 with a power density of 10,005 W kg−1 and prolonged cyclic life (capacitance retention of 79.19% after 8000 cycles). This study suggests N, S co-doping can further enhance the electrochemical performance based on high-SSA, which has a fine using prospect in the energy reserve side.