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Cu 2 ZnSnS 4 (CZTS) is regarded as one of the emerging materials for next-generation thin film solar cells. However, its synthesis is complex, and obtaining a single-phase CZTS thin film is difficult. This work reports the elaboration of Cu 2 ZnSnS 4 thin films by a sequential magnetron sputtering deposition of Cu 2 SnS 3 (CTS) and ZnS as stacked films. Initially, the CTS films were prepared on a soda lime glass substrate by annealing Cu and SnS 2 stacked layers. Second, ZnS was deposited by magnetron sputtering on the CTS films. The CTS\ZnS stacks were then annealed in Sn + S or S atmospheres. The tetragonal CZTS structure was obtained and confirmed by grazing incidence X-ray diffraction and Raman spectroscopy. The morphological and compositional characteristics, measured by scanning electron microscopy and energy-dispersive spectroscopy, revealed large grains and dense surfaces with the elemental composition close to the intended stoichiometry. Additional X-ray photoemission spectroscopy measurements were performed to determine the surface chemistry and particularities of the obtained films. The optical properties, determined using conventional spectroscopy, showed optimal absorber layer band gap values ranging between 1.38 and 1.50 eV. The electrical measurements showed that all the films are p-type with high carrier concentrations in the range of 10 15 to 10 20 cm –3 . This new synthesis route for CZTS opens the way to obtain high-quality films by an industry-compatible method.

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Nanoscale thermometers with high sensitivity are needed in domains which study quantum and classical effects at cryogenic temperatures. Here, we present a micrometer sized and nanometer thick chromium selenide cryogenic temperature sensor capable of measuring a large domain of cryogenic temperatures down to tenths of K. Hexagonal Cr-Se flakes were obtained by a simple physical vapor transport method and investigated using scanning electron microscopy, energy dispersive X-ray spectrometry and X-ray photoelectron spectroscopy measurements. The flakes were transferred onto Au contacts using a dry transfer method and resistivity measurements were performed in a temperature range from 7 K to 300 K. The collected data have been fitted by exponential functions. The excellent fit quality allowed for the further extrapolation of resistivity values down to tenths of K. It has been shown that the logarithmic sensitivity of the sensor computed over a large domain of cryogenic temperature is higher than the sensitivity of thermometers commonly used in industry and research. This study opens the way to produce Cr-Se sensors for classical and quantum cryogenic measurements.

In this study, manganese‐cobalt (MnCo) mixed oxide catalysts were prepared by two different routes: co‐precipitation and citrate method. The structures and properties of the mixed oxide catalysts were investigated by several techniques: nitrogen adsorption‐desorption isotherms, X‐ray diffraction, X‐ray photoelectron spectroscopy, SEM, FTIR and UV‐Vis spectroscopies, temperature‐programmed reduction with H2 (H2‐TPR) and temperature‐programmed desorption of NH3 (NH3‐TPD). Their catalytic performance was investigated in the liquid‐phase selective oxidation of naturally occurred p‐cymene to terephthalic acid, as an alternative to p‐xylene, a fossil derivative fuel component. Within this study, we demonstrate that the materials prepared by the co‐precipitation method present strong acid sites that boost the oxidation rate and allow oxidation of p‐cymene up to terephthalic acid. The co‐existence of a significant number of strong acid and centers in higher oxidation state (Co3+) are required for these materials to be selective.

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