Facile synthesis of NiMoO4·xH2O nanorods as a positive electrode material for supercapacitors

Abstract

NiMoO₄·xH₂O nanorods with one-dimensional structures and high performances are synthesized by a facile chemical co-precipitation method. A maximum specific capacitance of 1136 F g⁻¹ is achieved at a current density of 5 mA cm⁻². The fabricated NiMoO₄·xH₂O is a good positive electrode material for supercapacitors due to its unique structure and excellent capacitive properties. To enhance the energy density and enlarge the potential window, an asymmetric supercapacitor is assembled using NiMoO₄·xH₂O as the positive electrode and activated carbon (AC) as the negative electrode in 2 M aqueous KOH electrolyte. It exhibits a high energy density and stable power characteristics. A maximum specific capacitance of 96.7 F g⁻¹ and specific energy of 34.4 W h kg⁻¹ are demonstrated for a cell voltage between 0 and 1.6 V, indicating that the fabrication of an asymmetric supercapacitor is an effective way to enhance the energy density.