Binary transition metal oxide/carbon compounds-based electrode materials for supercapacitor application: A comprehensive review

Metal oxides have garnered widespread interest owing to their theoretical and experimental merits. Among these, binary transition metal oxides (BTMOs) represent a novel class of these metal oxides, recognized for their stability, cost-effectiveness, and superior efficiency as energy storage electrode materials. The advantages of BTMOs arise from the synergistic effects of incorporating a couple of transition metal oxides within their structure, coupled with their favorable electronic conductivity, which enhances their suitability for supercapacitor applications. Besides, the performance of BTMOs could be further augmented by integrating them with various porous and conductive substrates, such as diverse carbon structures, MXene, conductive polymers, or metal-organic frameworks (MOFs). This integration elevates the electrochemically active surface area and improves the electrical conductivity of BTMOs, thereby enhancing their energy storage capabilities. This review will examine the potential of BTMOs as supercapacitor electrodes and discuss recent advancements to improve the performance of these materials by incorporating additional carbon components into their structure.