Dataset of Operando Exploration of Tribochemical Decomposition in Synthetic FeS2 thin film and Mineral Iron Pyrite

Datasets of mass-spectrometry signals were obtained in the experiments with non-thermal tribochemical decomposition of synthetic thin-film iron sulphide and mineral iron pyrite. Tribochemical reactions were studied on a micrometre scale using localized rubbing under ultrahigh vacuum. Mechanically Stimulated Gas Emission Mass-Spectrometry (MSGE-MS) including the Dynamic gas expansion method was used to determine the kinetic parameters of gas emission and the composition of the emitted gases. The study was complemented by structural, morphological, tribological, mechanical and surface analyses. It was found that carbon-containing gases were dominating. The sulfur-containing gases comprised H2S, COS and CS2. The latter two were unexpected. The emission of these gases was traced back to solid-state chemical reactions kinetically controlled by the precursor concentrations and driven through non-thermal mechanisms, which we tentatively assigned to formation of sulfur radicals.