The combination of oxide and heavier chalcogenide layers in thin film photovoltaics suffers limitations associated with oxygen incorporation and sulfur deficiency in the chalcogenide layer or with a chemical incompatibility which results in dewetting issues and defect states at the interface. Here, we establish atomic layer deposition (ALD) as a tool to overcome these limitations. ALD allows one to obtain highly pure Sb2S3 light absorber layers, and we exploit this technique to generate an additional interfacial layer consisting of 1.5 nm ZnS. This ultrathin layer simultaneously resolves dewetting and passivates defect states at the interface. We demonstrate via transient absorption spectroscopy that interfacial electron recombination is one order of magnitude slower at the ZnS-engineered interface than hole recombination at the Sb2S3/P3HT interface. The comparison of solar cells with and without oxide incorporation in Sb2S3, with and without the ultrathin ZnS interlayer, and with systematically varied Sb2S3 thickness provides a complete picture of the physical processes at work in the devices.

Nanotubular iron(III) oxide electrodes are optimized for catalytic efficiency in the water oxidation reaction at neutral pH. The nanostructured electrodes are prepared from anodic alumina templates, which are coated with Fe O by atomic layer deposition. Scanning helium ion microscopy, X-ray diffraction, and Raman spectroscopy are used to characterize the morphologies and phases of samples submitted to various treatments. These methods demonstrate the contrasting effects of thermal annealing and electrochemical treatment. The electrochemical performances of the corresponding electrodes under dark conditions are quantified by steady-state electrolysis and electrochemical impedance spectroscopy. A rough and amorphous Fe O with phosphate incorporation is critical for the optimization of the water oxidation reaction. For the ideal pore length of 17 μm, the maximum catalytic turnover is reached with an effective current density of 140 μA cm at an applied overpotential of 0.49 V.

Hingganite from the Wanni glacier (Switzerland) was studied by means of energy dispersive and wavelength-dispersive spectroscopy, Raman spectroscopy, and low-temperature single-crystal X-ray diffraction. According to its chemical composition, the investigated mineral should be considered as hingganite-(Y). It showed a relatively high content of Gd, Dy, and Er and had limited content of lighter rare-earth element (REE), which is typical for Alpine gadolinite group minerals. The most intense Raman bands were 116, 186, 268, 328, 423, 541, 584, 725, 923, 983, 3383, and 3541 cm−1. Based on data of low-temperature [(−173)–(+7) °C] in situ single-crystal X-ray diffraction, it was shown that the hingganite-(Y) crystal structure was stable in the studied temperature range and no phase transitions occurred. Hingganite-(Y) demonstrated low volumetric thermal expansion (αV = 9(2) × 10−6 °C−1) and had a high thermal expansion anisotropy up to compression along one of the directions in the layer plane. Such behavior is caused by the shear deformations of its monoclinic unit cell.

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The high-pressure behavior of slawsonite, SrAl2Si2O8, has been studied using in situ single-crystal X-ray diffraction (SCXRD) and Raman spectroscopy up to 31 GPa. Slawsonite undergoes displacive phase transition between 6 and 8 GPa with the formation of slawsonite-II, featuring fivefold coordinated silicon and aluminum. The results have been confirmed by the changes in vibrational modes using Raman spectroscopy. High-pressure evolution of the Raman spectra of isotypic paracelsian, BaAl2Si2O8, was studied upon compression and decompression up to 37.5 GPa. Raman data for paracelsian upon compression are in good agreement with previously obtained SCXRD data, which demonstrated three phase transitions at ∼6, 28, and 32 GPa with the formation of AlO5, SiO5, AlO6, and SiO6 polyhedra. Raman data upon decompression show the possibility to quench the high-pressure modification, containing AlO5 polyhedra. The comparison of the high-pressure behavior of slawsonite with paracelsian reveals that the increasing size of extra framework cation from Sr2+ to Ba2+ reduces the phase transition pressure but does not change the transformation pathway.