Influence of Anatase-Rutile Ratio on Band Edge Position and Defect States of TiO2 Homojunction Catalyst

Removal of toxic air and water dissociation in the environment has become a major challenging issue throughout the world. Mixed phase rutile-anatase titanium dioxide catalysts are very effective in photocatalysis and have been studied extensively. However, the mechanism causing this effect and band alignment of the two phases are not fully understood. Pointing to the issue, we have designed one-dimensional mixed-phase TiO2 and introduced defects near the valence band. Experimental results showed that band alignment between two phases, up-shift of the band edge, and optimum anatase percentage play a key role in the enhancement of the photocatalytic activity. We predicted shifts in band edge originating from surface electric dipole layer induced by defects. [Display omitted] •Designed one dimensional mixed phase TiO2 Electrospun nanofiber and introduced selective defects near the valance band.•Mixed phase ratio and defect states control the photocatalytic redox activity.•Analyzed crystallite size and lattice strain using Scherrers, Willianson-Hall and Wagner-Agua Methods.