THE ELECTRONIC AND OPTICAL PROPERTIES OF X-DOPED SrTiO3 (X = Rh, Pd, Ag): A FIRST-PRINCIPLES CALCULATIONS

The electronic and optical properties of X-doped (X = Rh, Pd, Ag) cubic SrTiO3 in perovskite structure are investigated using first-principles calculations. The strength of the Ti-O bonds near the substitutional X impurity is found to be weakened by the shorter X-O bonds. Three types of electronic characteristics due to X-doping are demonstrated. X-doping decreases the band gap of SrTiO3, extending the optical absorption edge to visible light. Although Pd-doped SrTiO3 has the greatest absorption in the visible light region, its photocatalytic activity is lower than that of Rh-doped SrTiO3, because the intermediate bands from the 4d orbitals of the Pd dopant act as recombination centers. The theoretical results coincide with the available experimental results.