Perovskite SrZrO₃ as a Novel Material for Solar-Assisted Water Splitting

Developing novel electrodes for photocatalytic water splitting using computational analysis is a fascinating area of study with important implications for renewable energy generation. Perovskite SrZrO3 has been investigated as a potential catalyst for solar water splitting. Specifically, the synergistic effects of hydrogen doping and oxygen vacancies on the optoelectronic properties of the material have been revealed and discussed. First-principles calculations revealed that interstitial hydrogen defects are energetically favorable compared to substitutional hydrogen in SrZrO3. Moreover, mono- and co-hydrogen occupied oxygen vacancies have also been examined. Hydrogen doping was shown to introduce shallow defect states below the conduction band minimum, which could be beneficial for applications like gate dielectrics. At high oxygen vacancy concentrations, the HOV-OV structural configuration exhibited localized shallow defect states with a 1.3 eV band gap energy, increased dielectric constant, and enhanced optical absorption compared to pristine SrZrO3. This HOV-OV structure was identified as an ideal novel candidate catalyst for photocatalytic water splitting, based on factors such as Gibbs free energy, band gap alignment, low exciton binding energy, and high permittivity. Overall, this computational work provides valuable insights into engineering the optical and electronic properties of SrZrO3 through strategic defect incorporation. The findings could help guide the experimental development of high-performance photocatalysts for renewable hydrogen production.