Controllable synthesis of ZIF-derived nano-hexahedron porous carbon for supercapacitor electrodes

The nano-hexahedron porous carbon was prepared by directly carbonizing a Zn-based zeolitic imidazolate framework (ZIF-8) at designed temperatures. After carbonization, the nano-hexahedron porous carbon shows a large specific surface area of 1142 m(2) g(-1) at a pore diameter of approximate 3 nm, a high capacitance of 187 F g(-1), a remarkable rate-capability of 75.9%, and an unchangeable capacitance retention after 10,000 cycles. Furthermore, the symmetrical supercapacitor exhibits a high energy density of 9.04 Wh kg(-1) at a power density of 350 W kg(-1) and a notable capacitance retention of 80.2% after 5000 cycles. All results have suggested that the nano-hexahedron porous carbon is adaptable to the assembly of effective electrode materials for supercapacitors. (C) 2019 Elsevier B.V. All rights reserved.