Cu-MOFs derived three-dimensional Cu1.81S@C for high energy storage performance

Significant volume changes and slow ionic transport during charge/discharge processes restrict the improvement of electrochemical performance for Cu x S (x = 1–2). Herein, a new strategy by introducing Cu-BTC (copper(II)-benzene-1,3,5-tricarboxylate) as a processor to derive three-dimensional Cu 1.81 S@C using green sulfurization and calcination methods is proposed. Benefiting from the high electrical conductivity , multistage pore size structure and stable structure brought by the conductive carbon skeleton after calcination , Cu 1.81 S@C-650 o C exhibits a high specific capacitance of 291.1 F g -1 at a current density of 1 A g -1 and a superior rate capability of 83.6 % at a current density of 10 A g -1 . In addition, the assembled asymmetric supercapacitor (Cu 1.81 S@C-650 o C//AC ASC) also shows impressive performances, such as an energy density up to 16 Wh kg -1 at a power density of 352 W kg -1 and an excellent cycling stability of 93.1 % over 5000 cycles at a current density of 2 A g -1 . This work demonstrates that the Cu-BTC-derived Cu 1.81 S@C is an attractive material with potential applications in energy storage devices.