<p>Zn_xCe_1-xVO₄ nanoparticles were prepared via a sol–gel auto-combustion method, providing a simple, economical, and eco-friendly approach. XRD confirmed the formation of a tetragonal zircon-type crystal structure with high phase purity, while FTIR revealed characteristic metal–oxygen bonding vibrations, validating the successful formation of the vanadate. FESEM coupled with EDX displayed homogeneous elemental distribution and uniform nanoparticle morphology, further supported by TEM and SAED, which confirmed nanoscale dimensions and polycrystalline nature. The CV profiles exhibited distinct redox peaks, confirming pseudocapacitive behaviour originating from reversible faradaic reactions. The tetragonal zircon-type crystal structure of Zn_xCe_1-x VO₄ nanoparticles facilitates fast ion transport and reversible redox processes, enabling a high specific capacitance of 449 F g⁻¹ at 1 A g⁻¹, along with an energy density of 89.8 W h kg⁻¹ at a power density of 599.77 W kg⁻¹. The electrode exhibited remarkable cycling stability, maintaining 87.01% of its original capacitance after 3000 successive charge–discharge cycles. These findings highlight the synergistic effect of Zn doping and nanoscale morphology improves ion transport and electron transfer, demonstrating a sustainable strategy for designing high-performance pseudocapacitive materials for energy storage applications.</p>