This study employed the ball milling process to successfully craft nanostructures of Cu-doped ZnO/SnO2 (ZOSn/Cu), which were thoroughly characterized through various methods. The X-ray diffraction (XRD) analysis revealed the presence of the Zn2SnO4 cubic spinel phase in the nanostructure samples, along with diffraction peaks corresponding to ZnO or SnO2 phases. Notably, the photocatalytic degradation performance of the structured catalysts was greatly improved compared to undoped ZOSn/Cu nanostructures, achieving MB elimination rates of 60% and 80% after 120 min of irradiation, with an overall degradation of approximately 90%. The ZOSn/Cu electrode, designed for energy storage, demonstrated superior performance, boasting a specific capacitance of 380.0 Fg−1, outperforming the pure ZOSn/Cu electrode. Its trimetallic composition of zinc, copper, and tin contributed to enhanced electrochemical properties. This electrode demonstrated excellent cyclic stability, maintaining around 90% of its capacity, along with key characteristics like corrosion resistance, high conductivity, and a wealth of active sites. These properties make it highly promising for advanced energy storage applications.