# Effects of La-N Co-Doping of BaTiO3 on Its Electron-Optical Properties for Photocatalysis: A DFT Study

## TL;DR

This study uses DFT calculations to show that co-doping BaTiO3 with La at the Ti site improves its visible light absorption and photocatalytic water-splitting ability.

## Contribution

The novel contribution is demonstrating how La doping at the Ti site in BaTiO3 enhances photocatalytic performance through intermediate energy levels.

## Key findings

- Co-doping BaTiO3 with 25% La at the Ti site increases visible light absorption and photocatalytic water-splitting efficiency.
- La doping introduces intermediate energy levels that reduce the energy required for electronic transitions in BaTiO3.

## Abstract

In cation–anion co-doping, rare earth elements excel at regulating the electronic structure of perovskites, leading to their improved photocatalytic performance. In this regard, the impact of co-doping rare earth elements at the Ba and Ti sites in BaTiO3 on its electronic and photocatalytic properties was thoroughly investigated based on 2 × 2 × 2 supercell structures of BaTiO3 with different La concentrations of 12.5% and 25% using DFT calculations. The band structure, density of states, charge density difference, optical properties, and the redox band edge of the co-doped models mentioned above were analyzed. The results indicated that the BaTiO3 structure co-doped with 25% La at the Ti site exhibited higher absorption in the visible range and displayed a remarkable photocatalytic water-splitting performance. The introduced La dopant at the Ti site effectively reduced the energy required for electronic transitions by introducing intermediate energy levels within the bandgap. Our calculations and findings of this study provide theoretical support and reliable predictions for the exploration of BaTiO3 perovskites with superior photocatalytic performances.