Towards an efficient perovskite visible-light active photocatalyst

TL;DR

This study uses density functional theory to explore how co-doping SrTiO3 with specific elements can modify its electronic structure, aiming to develop more efficient visible-light photocatalysts.

Contribution

It identifies that Mo and Zn co-doping in SrTiO3 can enhance photocatalytic activity by optimizing band structure and optical properties.

Findings

Mo, Zn co-doped SrTiO3 shows potential for improved photocatalysis.

Ta, Ga/In co-doping does not enhance photocatalytic activity.

Mo, Cd doping impedes photocatalytic efficiency.

Abstract

The band gap of SrTiO$_{3}$ retards its photocatalytic application. Regardless narrowing the band gap of the anion doped SrTiO$_{3}$, the anion doping structures have low photoconversion efficiency. The co-cation dopings are used to modify the band gap and band edges positions of SrTiO$_{3}$ to enhance the photocatalyitic properties by extending the absorption to longer visible-light. Using density functional calculations with the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional for exchange-correlation, the crystal and electronic structures as well as the optical properties of the mono and codped SrTiO$_{3}$ are investigated. The (Mo, Zn/Cd) and (Ta, Ga/In) codoped SrTiO$_{3}$ are explored in the way to retain the semiconductor characteristics of the latter. It is found that (Ta, Ga/In) codoping does not enhance the photocatalytic activity of SrTiO$_3$ due to its large band gap. Moreover, the position of the conduction band edge of the (Mo, Cd) monodoping impedes the photocatalytic efficiency. The obtained results indicate that (Mo, Zn) codoped SrTiO$_3$ can potentially improve the photocatalyitic activity.