Explosive effect-assisted synthesis of hierarchical porous carbon for high-performance aqueous Zn-ion hybrid supercapacitors with commercial level mass loading

Abstract

Aqueous Zn-ion hybrid supercapacitors (AZHCs) are potential types of energy storage applications that combine the advantages of supercapacitors and batteries. The low mass loading and poor rate performance of cathodes, however, severely limits their practical application. Herein, an explosive effect assisted strategy is reported for the efficient synthesis of N, O co-doped porous carbon nanosheets (NPCNs) by synergistic activation of high-quality soft carbon precursor perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) with KOH and Zn(NO3)2. Benefiting from the comprehensive modulation of the morphology, pore structure, and surface chemistry, the obtained NPCNs show the significant enhancement in diffusion kinetics. Consequently, the as-fabricated AZHCs exhibited remarkably improved Zn-ion storage capability (189.3 mAh g−1 at 0.1 A g−1, 96.7 mAh g−1 at 20 A g−1) and long-term cycling stability at 20 A g−1 (∼ 92.5 % retention upon 6000 cycles). Moreover, NPCNs also deliver a superb areal capacity of 1.6 mAh cm−2 with a mass loading of 15.4 mg cm−2. Most importantly, we demonstrate that such porous carbon framework with competent electrochemical properties can be easily produced from diverse soft carbon precursor. This work thus introduces a universal and efficient strategy to produce high-performance porous carbon electrode materials for AZHCs.