Single‐Step One‐Pot Synthesis of NiCo 2 O 4 /Molybdate Nanocomposites for Flexible Supercapacitor Electrodes

Energy storage technology plays a critical role in integrating variable energy sources into the grid and ensuring energy consistency. Electrochemical supercapacitors are one of the most promising energy storage devices, as they present multiple advantages of high power density, rapid charge/discharge characteristics, and long‐term cycle stability. Herein, the NiCo 2 O 4 /molybdate nanocomposites are developed as electrode materials for supercapacitor applications. The NiCo 2 O 4 /molybdate nanocomposites are synthesized by a facile single‐pot hydrothermal method and are coated on a carbon cloth substrate to form flexible supercapacitor electrodes. The structures, chemical compositions, morphologies, and textural properties of these materials are carefully studied by X‐Ray diffraction, X‐Ray absorption spectroscopy, scanning electron microscopy/energy‐dispersive X‐Ray spectroscopy mapping, and N 2 adsorption–desorption isotherms. The formation of spinel NiCo 2 O 4 nanorods decorated with molybdate (AMoO 4 , A = Co, Ni) particles is confirmed for all samples. The NiCo 2 O 4 /CoMoO 4 electrode exhibits pseudocapacitive behavior and provides the highest specific capacitance (287.28 F g −1 at current density 6 A g −1 ), about 5.5 times as high as that of NiCo 2 O 4 , with excellent cycle stability (107% specific capacitance retention after 1000 charge/discharge cycles at 1 A g −1 ). Therefore, the NiCo 2 O 4 /CoMoO 4 composites can be considered as a promising pseudocapacitor electrode material.