High-Performance Pseudocapacitive Electrode Based on Electrophoretically Deposited NiCo 2 O 4 /MWCNTs Nanocomposite on 316L Stainless Steel

Nickel cobaltite (NiCo 2 O 4 ) nanorods with spinel structure have been synthesized using a template-free hydrothermal method. The structure and morphology of the as-prepared nanorods were studied by x-ray diffraction analysis, field-emission scanning electron microscopy, and nitrogen adsorption–desorption measurements. Binder-free NiCo 2 O 4 and NiCo 2 O 4 /carbon nanotube electrodes were fabricated via an electrophoretic deposition (EPD) procedure then subjected to electrochemical evaluation using cyclic voltammetry and galvanostatic charge–discharge measurements. The results revealed that the pseudocapacitive performance was enhanced by introducing CNTs into the NiCo 2 O 4 electrode. Compared with the pure NiCo 2 O 4 electrode, the composite electrode exhibited excellent energy storage performance with high specific capacitance of 1540 F g −1 at 3.5 A g −1 , good rate performance with capacitance of 664 F g −1 even at high current density of 7.5 A g −1 , and reasonable cycling performance (73% capacitance retention after 3000 cycles).