Optimization of macropore evolution towards high photocatalytic activity enhancement in meso/macro porous Anatase TiO₂

We report on an optimization strategy for macro pore evolution leading to the design of highly photocatalytic 3D hierarchical meso/macroporous TiO₂ via much simpler, faster and cost effective synthesis scheme. Meso/macro porous TiO₂ is an excellent candidate material for photocatalytic applications owing to the availability of internal surfaces as active sites for redox reactions. The current research scenario focuses on the design of highly efficient photocatalytic systems as well as rapid, facile and cost effective methods of synthesis and optimization of parameters. The present report is on the gradual evolution of macropores in anatase TiO₂ by the effective control of pH of the solvent, reaction time, temperature, solvent ratio and reactant concentration via a facile hydrothermal method in this regard. 3D hierarchical macroporous structures are obtained at pH 7 within a comparatively short reaction time of 5 h and demonstrated to be highly photocatalytic (with rate constant four times that of P25 nanoparticles) through photodegradation of Rhodamine B dye. (paper)