TiO2–SiO2 nanoparticles are promising materials for energy storage devices, but optimization of the stability,
particle size, and electrochemical performance is still a challenge. The optimal synthesis conditions were
determined for TiO2–SiO2 nanoparticles at ratio of 1:1, pH 1, synthesis temperature of 35 ◦C, and 2 % PVA. Under
these all-post optimization conditions, the nanoparticles exhibited enhanced stability (􀀀 23.26 mV) and minimized
hydrodynamic size (189 nm) as confirmed by dynamic light scattering, along with a slight increase in the
band gap. Electrochemical studies revealed superior performance, with the optimized NPs achieving a specific
capacitance of (1038 F/g at 2.5 A/g), which significantly higher than unoptimized nanoparticles and previously
reported similar nanoparticles. Furthermore, raising the specific power to 537.5 W kg􀀀 1 resulted in a remarkable
specific energy of 26.67 Wh.kg􀀀 1 proving its high energy, and power density. These results highlight the necessity for controlling synthesis parameters to realize the desired materials’ properties as optimized TiO2–SiO2 nanoparticles featured excellent stability and energy storage performance.