Synthesis-Controlled Interfacial Engineering of Reduced Graphene Oxide–Transition Metal Oxide Nanocomposites for High-Efficiency Supercapacitors: A Review

The increasing reliance on nonrenewable fossil fuels presents a substantial threat to global sustainability, necessitating the development of renewable, cost-effective, and environmentally sustainable energy storage solutions. Supercapacitors offer high power density, robust cycle stability, and rapid charge-discharge capabilities, yet their energy density remains lower than that of conventional batteries. The performance of supercapacitors is largely determined by the properties of the electrode materials used, underscoring the critical role of material innovation in addressing the limitations of fossil fuel consumption. Reduced graphene oxide (rGO) exhibits high electrical conductivity, chemical stability, a large specific surface area, and an advantageous mesopore-size distribution, all of which contribute to superior electrical performance. Transition metal oxide (TMO) offers efficient charge storage and release. Recent advances have shown that integrating rGO with TMO yields synergistic improvements in electrical conductivity, surface area, and charge storage capacity. This study provides a comprehensive analysis of current studies and offers perspectives on future developments, thereby advancing the field of electrode materials for energy storage applications.