Surface spectroscopy studies of the SrTiO3 (100) surface and the platinum-SrTiO3 (100) interface

Auger-electron spectroscopy (AES), low-energy-electron diffraction (LEED), electron-energy-loss spectroscopy (ELS), and ultraviolet-photoelectron spectroscopy (UPS) were used to characterize the composition, structure, and electronic properties of the strontium-titanate (100) surface and the platinum strontium-titanate interface. The strontium 65-eV Auger signal on the clean strontium-titanate surface decreases abruptly as the temperature is raised beyond 240°C. Partial ordering occurs when platinum is deposited on the strontium-titanate (100) surface as evidenced by LEED. Platinum appears to remove surface Ti3+ by electron transfer from SrTiO3 to platinum. These results are discussed in light of the findings in photoelectrolysis and other photocatalytic studies using SrTiO3.