New insight into the enhanced photocatalytic activity of Al-, C- and Al-C co doped rutile TiO2 photocatalysts

Abstract

TiO2 has been proven to be the most suitable photocatalytic materials for wide environmental and energy applications because of its suitable valence band and conduction band positions, long-term stability, non-toxicity, cost-effectiveness and strong oxidizing power. Based on the first-principles density functional theory calculations in the framework of density functional theory, the crystal structure, electronic properties, optical properties and photocatalytic activity of photocarriers in Al- doped, C- doped and Al-C co-doped rutile TiO2 systems were investigated. The results show that doping changes the local density and electronic property of rutile TiO2 around the Fermi level. Doping can improve the optical absorption capacity of TiO2 and enlarge its response range to visible light. In addition, the larger of the relative effective mass of photogenerated hole electrons indicates the smaller recombination probability of photogenerated carriers and the higher light catalytic activity. This work will provide some new ideas for understanding the differences in photocatalytic activity between Al- doped, C- doped and Al-C co-doped rutile TiO2, and also provide a new direction for the study of metal and non-metal doped rutile TiO2.