Solid-state chemical fabrication of one-dimensional mesoporous β-nickel molybdate nanorods as remarkable electrode material for supercapacitors.

Simple solid-state chemical reaction was adopted to synthesize NiMoO4 nanomaterials with different crystal phase without the use of organic solvent or templating agent. The as-prepared NiMoO4·xH2O, α-NiMoO4 and β-NiMoO4 nanostructures were investigated as the electrode materials for supercapacitors. The β-NiMoO4 nanorods were composed of the nanoparticles, which exhibited relatively high specific capacitances about 1415 F g-1 at a charge density of 1 A g-1, 80.2% of the initial reversible capacity was maintained after 1000 cycles. The β-NiMoO4//rGO asymmetric supercapacitor (ASC) system was assembled in serials, which displayed high specific energy density of 29.3 Wh kg-1 at a high power density of 187 W kg-1. This ASC system can drive the light-emitting diode (LED) effectively and give out light about 40 min, even easily light two LEDs in serials for 20 min. The remarkable electrochemical performances make the as-prepared NiMoO4 nanostructures an excellent candidate as electrode materials for advanced supercapacitors.