摘要
ZIF-derived carbon structures are considered as desired electrode materials for supercapacitors due to their high surface area,high conductivity, and porous structure. However, the most reported ratio of 2-methylimidazole and Zn(II) is 4:1 to 20:1, which limits commercial applications due to the increasing cost. In this paper, a multirole Zn(II)-assisted method is presented from Zn(II) solution, Zn O, Zn O/ZIF-8 core-shell nanostructure, to 3 D hierarchical micro-meso-macroporous carbon structures with a1:1 ratio of 2-methylimidazole and Zn(II). The hierarchically porous carbon has a high surface area of 1800 m2 g^(-1) due to the synergistic effect of multirole Zn(II). The unique carbon-based half-cell delivers the specific capacitances of 377 and 221 F g^(-1) at the current densities of 1.0 and 50 A g^(-1), respectively. As a 2.5 V symmetrical supercapacitor, the device reveals a high doublelayer capacitance of 24.4 F g^(-1), a power density of 62.5 k W kg^(-1), and more than 85.8% capacitance can be retained over 10000 cycles at 10 A g^(-1). More importantly, the low-cost hierarchically porous carbon could be easily produced on a large scale and almost all chemicals can be reused in the sustainable method.
基金
supported by the National Natural Science Foundation of China (Grant Nos. U1832136,21303038)
the Think-Tank Union Funds for Energy Storage (Grant No. JZ2016QTXM1097)
the 100 Talents Program of Anhui Province
Natural Science Foundation of Anhui province (Grant No. 1808085QE140)。
