Structure and photocatalytic performance of TiO₂ nanoparticles prepared by the coupling of microemulsion and sol-gel methods

TiO₂ nanoparticles were prepared by a sol-gel process in a microemulsion consisting of TX-100, w-pentanol, n-hexane and water. The influence of molar ratio of water to surfactant triton X-100 (r₂), molar ratio of water to n-tetrabutyl titanate (n-TBT) (r₁), molar ratio of TX-100 to n-hexane (V), molar ratio of n-hexanol to TX-100 (r₄) and molar ratio of acetylacetone to n-TBT (r₃) on the hydration of n-TBT and the subsequent reactions in the microemulsion were systematically investigated. The results showed that the appropriate conditions that realize the coupling of microemulsion and sol-gel processes, are as follow; r₂=3.00-6.00, r₁=3.00-4.00, r₃=0.20-0.40, r₄=4.00-6.00 and V=0.25-0.50. The average sizes of TiO₂ particles were around 12-26 nm. The best photocatalytic performance of TiO₂ particles is obtained with a degradation rate of 82.16% under the conditions of r₁=4.00, r₄=4.00, V=0.34, r₃=0.25 and r₂=3.00.