Three-Dimensional NiMoO4 Nanosheets Supported on a Carbon Fibers@Pre-Treated Ni Foam (CF@PNF) Substrate as Advanced Electrodes for Asymmetric Supercapacitors.

Herein, we report a nanoarchitectured nickel molybdate/carbon fibers@pre-treated Ni foam (NiMoO4/CF@PNF) electrode for supercapacitors. The synthesis of NiMoO4/CF@PNF mainly consists of a direct chemical vapor deposition (CVD) growth of dense carbon fibers (CFs) onto pre-treated Ni foam (PNF) as the substrate, followed by in situ growth of NiMoO4 nanosheets (NSs) on the CF@PNF substrate by means of a hydrothermal process. The NiMoO4/CF@PNF electrode exhibits a high areal capacitance (5.14 F cm−2 at 4 mA cm−2) and excellent cycling stability (97 % capacitance retention after 2000 cycles at 10 mA cm−2). Furthermore, we have successfully assembled NiMoO4 NSs//activated carbon (AC) asymmetric supercapacitors, which can achieve an energy density of 45.6 Wh kg−1 at 674 W kg−1, and excellent stability with 93 % capacitance retention after 2000 cycles at 5 mA cm−2. These superior properties hold great promise for energy-storage applications. [ABSTRACT FROM AUTHOR]