Morphology Effect on Electrocatalytic Activity of TiO₂ Spheres Synthesized by Binary Ionic Liquids in Water Electrolysis

摘要

Titania spheres were synthesized using binary ionic liquids to examine the electrocatalytic activity in acid solution. The morphology of TiO2 particles was significantly different with the composition of ionic liquids. Among the binary ionic liquids, four set of mixtures led to the formation of TiO2 sphere with various sizes. The morphology and structure of TiO2 particles were characterized by XRD, N2 physisoption and SEM analysis. All samples possessed an anatase phase after calcinations at 500 oC. The structural properties of the samples were varied significantly with the morphology. In cyclic voltammograms, the morphology of TiO2 spheres affected the electrocatalytic activity in water electrolysis. Among the samples, [Omim][BF4]+[Hmim][BF4] was the most effective ionic liquid to synthesize TiO2 sphere with optimum morphology showing the highest electocatalytic performance.