XPS data from The effect of Mn doping and Ti³⁺ defects at TiO₂ surfaces in NO and SO₂ gas capture investigated using near-ambient pressure X-ray photoelectron spectroscopy

Some oxidising air pollutants, such as NOx and SO2 are thought to be linked to premature skin aging. Here we study a model system of titanium dioxide (TiO2) single crystals with and without Mn doping, in order to understand the reaction mechanism and amount of adsorbed gas. We also investigate the effect of O-vacancies formed on the TiO2 surface. We find that Mn leads to an increased uptake of both gases and conversion to sulphite and sulphate. We also find increased surface O-vacancies results in a larger Mn uptake. We then compare these data to reaction of the pollutant gases with two commercial TiO2 powders used in cosmetic products with and without Mn, and although the products are subtly different the uptake is still increased for the Mn-doped sample. The data here are X-ray photoelectron spectra recorded from the different surface treatents and gas exposures.