High electrochemical energy storage performance of controllable synthesis of nanorod Cu1.92S accompanying nanoribbon CuS directly grown on copper foam.

Facile in-situ etching current collector prepares corresponding oxide or sulfide, which is directly used as faradic electrode material, supplying faster electron transportation and better connection, and thus displaying good supercapacitor performance. Here, we prepare Cu x S via etching copper foam and investigate the influence of etching time on the morphology and electrochemical performance. The results show that compared with the nano-rod Cu x S-1h/CF, nano-rod/wire Cu x S-2h/CF and block/nanorod Cu x S-4h/CF, the nano-rod/ribbon Cu x S-3h/CF electrode exhibits the highest specific capacity (448.8C g −1 at current density of 5 mA cm −2 ). We fabricate asymmetric supercapacitor based on Cu x S-3h/CF as positive electrode and AC as negative electrode to further evaluate the supercapacitor property and the device achieves a high energy density of 35 Wh kg −1 at power density of 266 W kg −1 . Furthermore, the outstanding cycling stability of 88% capacitance retention after 5000 charge-discharge cycles more enable the Cu x S-3h/CF become promising faradic electrode material. [ABSTRACT FROM AUTHOR]