Understanding the Interactions of CO2 with Doped and Undoped SrTiO3

SrTiO₃ and doped SrTiO₃ have a wide range of applications in different fields. For example, Rh-doped SrTiO3 has been shown to have photocatalytic activity for both hydrogen production and CO₂ conversion. In this study, both undoped and Rh-doped SrTiO₃ were synthesized by hydrothermal and polymerizable complex methods. Different characterizations techniques including X-ray photoelectron spectroscopy (XPS), XRD, Raman, and UV/Vis spectroscopy were utilized to establish correlations between the preparation methods and the electronic/structural properties of Rh-doped SrTiO₃. The presence of dopants and oxygen vacancies substantially influenced the CO₂ interactions with the surface, as revealed by the in situ infrared spectroscopic study. The presence of distinctly different adsorption sites was correlated to oxygen vacancies and oxidation states of Ti and Rh.