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AgInSe2 is a promising direct bandgap thin-film material with a rare n-type conductivity. Similar to thin film photovoltaic materials such as Cu(In,Ga)Se2 (CIGSe), which have achieved efficiencies as high as ~23%, AgInSe2 also crystallizes in a chalcopyrite phase while also being more tolerant to antisite defects due to higher defect formation energies resulting from more significant variations in cation sizes. AgInSe2 has a suitable bandgap of 1.24 eV, which lies in the high-efficiency region of the detailed balance limit. In this work, we have utilized a Dimethyl Formamide-Thiourea-Chloride-based solution-processed route to deposit a thin film of AgInS2 which is converted into AgInSe2 after a heat-treatment step in a selenium environment. AgInSe2 optoelectronic properties depend on the Ag/In ratio and the selenium heat-treatment conditions. Significant improvements in photoluminescence yield and lifetime are observed for Ag-poor films in selenium-rich conditions. X-ray Photoelectron Spectroscopy (XPS) measurements confirm a higher amount of selenium on the surface of films with improved optoelectronic properties. Furthermore, a high minority carrier lifetime of 9.2 ns and a Photoluminescence Quantum Yield (PLQY) of 0.013% is obtained without any passivating layer, which improved to 0.03% after CdS passivation. Hall effect measurements confirm that AgInSe2 has n-type conductivity with a moderate carrier concentration (10-14 cm-3), more suitable for a p-i-n architecture. XPS has further confirmed the moderate n-type conductivity. 

In this study, we show how strong metal–support interaction (SMSI) oxides in Pt–Nb/SiO 2 and Pt–Ti/SiO 2 affect the electronic, geometric and catalytic properties for propane dehydrogenation. Transmission electron microscopy (TEM), CO chemisorption, and decrease in the catalytic rates per gram Pt confirm that the Pt nanoparticles were partially covered by the SMSI oxides. X-ray absorption near edge structure (XANES), in situ X-ray photoelectron spectroscopy (XPS), and resonant inelastic X-ray scattering (RIXS) showed little change in the energy of Pt valence orbitals upon interaction with SMSI oxides. The catalytic activity per mol of Pt for ethylene hydrogenation and propane dehydrogenation was lower due to fewer exposed Pt sites, while turnover rates were similar. The SMSI oxides, however, significantly increase the propylene selectivity for the latter reaction compared to Pt/SiO 2 . In the SMSI catalysts, the higher olefin selectivity is suggested to be due to the smaller exposed Pt ensemble sites, which result in suppression of the alkane hydrogenolysis reaction; while the exposed atoms remain active for dehydrogenation.