Microphase Separation Engineering toward 3D Porous Carbon Assembled from Nanosheets for Flexible All-Solid-State Supercapacitors
Ning Wang, Guoli Zhang, Taotao Guan, Juncheng Wu, Jianlong Wang, Kaixi Li
Abstract
Although hierarchitectures could energize carbon materials to address the challenges encountered in emerging flexible energy storage, how to make the trade-offs among specific surface area, pore configuration, and conductivity is still a lingering issue. Herein, 3D porous carbon assembled by nanosheets (HCAs) with tunable hierarchical porous structure is acquired from amphiphilic coal tar pitch and chitosan by means of a facile microphase separation strategy without any templates. The polar molecular chains of chitosan and the surrounding pitch molecules with strong π–π* bonds self-assemble respectively to form hierarchical pores and a network of nanosheets in a stepped pyrolysis process. Due to the combined effects of the meso-dominant porous structure, high specific surface area, and nitrogen-rich nature, the as-assembled symmetric all-solid-state supercapacitor with a wide voltage range of 0–1.8 V delivers a specific capacitance of 296 F g–1 at 0.2 A g–1 and an energy density of 27 Wh kg–1 at a power density of 450 W kg–1. The strategy of microphase separation is proposed originally to design and to fabricate carbon materials with multilevel nanoarchitectural trade-offs for high-performance supercapacitors.