Si/NiCo2O4 heterostructures electrodes with enhanced performance for supercapacitor

Silicon doped metal oxides are potential materials for high-performance electrochemical energy storage because of the synergistic effect. In this work, Si/NiCo2O4 heterostructures have been successfully synthesized by a two-step solution-phase method. The characterizations demonstrate that the Si nanoslices dispersed uniformly in NiCo2O4. Serving as electrochemical electrode, the Si/NiCo2O4 heterostructures present high specific capacitance of 1972.1 F g−1 at a current density of 2 A g−1 and excellent reversibility with a cycling efficiency of 78% after 2000 cycles, which is approximately two times higher than that of NiCo2O4. The outstanding electrochemical performance is mainly attributed to the Si doping effect and synergistic effect between Si and NiCo2O4. This work suggests a way to design silicon doped electrode materials with enhanced performance for supercapacitors.