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Organo–inorganic halide perovskites continue to generate enormous interest for their potential use in various optoelectronic devices. Among the different fabrication methods, vacuum thermal deposition allows uniform films over large areas, providing good material quality without using organic solvents. However, the influence of the substrate on the properties of the material deposited by vacuum processing is a point that deserves further investigation. Herein, time‐dependent photoconductivity measurements are used to investigate the dynamics of charge carriers under illumination in planar films of CH3NH3PbI3. The samples are deposited by thermal sublimation on different substrates: PbI2, TaTm, C60, and glass. Experimentally, it is shown that the substrate has a profound effect on perovskite behavior and that photoconductivity is sensitive enough to probe these behaviors. Furthermore, a model based on Shockley–Read–Hall statistics is proposed, explaining the different photoconductivity responses by changing only the relative values of the different capture coefficients and the position of the Fermi level. It is argued that the substrate changes the stoichiometry of the evaporated material, affecting the transient photoconductivity response. [ABSTRACT FROM AUTHOR]

Deep‐sea sediments record palaeoenvironmental and oceanographic changes over time through variations in their magnetochemical and sedimentological properties. This study presents the Late Quaternary sedimentary reconstruction of three sediment cores extracted from a source‐to‐sink sedimentary system located in a high marginal platform of the north‐west Iberian Margin. The aim of this reconstruction is to explore the palaeoclimatic, palaeoproductivity and diagenetic changes over the last 172 cal ka bp attending to geochemical, magnetic and sedimentological variations. The record is comprised of four sedimentary units consisting of pelagic, hemipelagic and detrital facies, the latter associated with ice‐rafted debris events at Heinrich Stadials. These findings allowed the reconstruction of the lithostratigraphy attending to climatic changes, covering the last eleven Heinrich Stadials. These units and facies successions are controlled by the superposition of the Milankovitch and Dansgaard–Oeschger cycles. Low sedimentation rates have been reported, especially during cold periods. Palaeoproductivity was assessed using total organic carbon and calcium carbonate content, together with biogenic barium (Babio) and organic phosphorus (Porg), both calculated via total digestion analysis using standard calculations. Mass accumulation rates for total organic carbon, Babio and Porg were calculated. Furthermore, a sequential extraction was performed to explore the different phases of the barium within sediments: biogenic barite (Babar), barium associated with iron and manganese oxides (Baox) and Ba associated with aluminosilicates (Badet). Results display a limitation in the use of the biogenic barium and phosphorus and mass accumulation rates, suggesting detrital Ba (Badetr) contribution during Heinrich Stadials, which could mask the calculations. In contrast, only calcium carbonate fluctuates attending to glacial/interglacial cycles. Regarding some diagenetic proxies (i.e. Mn, Mn/Fe and Mn/Ti), they reveal oxidation fronts of different generations, suggesting that the early diagenesis has not reached steady‐state, because the redoxcline fluctuates. This fact suggests an erosional activity that causes the continuous oxygenation of the sediment and non‐steady‐state conditions. [ABSTRACT FROM AUTHOR]

Metal halide perovskite solar cells (PSCs) are of interest for high altitude and space applications due to their lightweight and versatile form factor. However, their resilience toward the particle spectrum encountered in space is still of concern. For space cells, the effect of these particles is condensed into an equivalent 1 MeV electron fluence. The effect of high doses of 1 MeV e‐beam radiation up to an accumulated fluence to 1016 e− cm−2 on methylammonium lead iodide perovskite thin films and solar cells is probed. By using substrate and encapsulation materials that are stable under the high energy e‐beam radiation, its net effect on the perovskite film and solar cells can be studied. The quartz substrate‐based PSCs are stable under the high doses of 1 MeV e‐beam irradiation. Time‐resolved microwave conductivity analysis on pristine and irradiated films indicates that there is a small reduction in the charge carrier diffusion length upon irradiation. Nevertheless, this diffusion length remains larger than the perovskite film thickness used in the solar cells, even for the highest accumulated fluence of 1016 e− cm−2. This demonstrates that PSCs are promising candidates for space applications. [ABSTRACT FROM AUTHOR]

Herein, the dehydration of a hydrogen molybdenum bronze (HYMoO3), converting it to molybdenum oxide (MoOX), is explored toward the development of perovskite solar cells (PSCs) for the first time. H0.11MoO3 bronze is synthesized, characterized, and deposited on indium tin oxide (ITO) under different concentrations and annealing conditions for in situ conversion into MoOX with appropriate oxygen vacancies. Vacuum‐deposited PSCs are fabricated using the as‐produced MoOX hole injection layers, achieving a power conversion efficiency of 17.3% (average) for the optimal device. The latter has its stability and reproducibility tested, proving the robustness and affordability of the developed hole transport layer in PSCs. [ABSTRACT FROM AUTHOR]

Efficient monolithic perovskite/perovskite tandem solar cells are fabricated using two perovskite absorbers with complementary bandgaps. By employing doped organic semiconductors, an efficient and selective extraction of the charge carriers is ensured. This study demonstrates perovskite/perovskite tandem cells delivering a maximum efficiency of 18%, highlighting the potential of vacuum‐deposited multilayer structures in overcoming the efficiency of single‐junction perovskite devices. [ABSTRACT FROM AUTHOR]

In a recent proteomics study we have shown that themcbRgene ofCorynebacterium glutamicumATCC 13032 most probably encodes a transcriptional repressor of the TetR type, which regulates the expression of at least six genes involved in the synthesis of sulphur-containing amino acids. By means of DNA microarray hybridizations we detected 86 genes with enhanced transcription in anmcbRmutant when compared with the wild-type strain. Bioinformatic analysis identified the inverted repeat 5′-TAGAC-N6-GTCTA-3′ as a consensus sequence within the upstream region of 22 genes and operons, suggesting that the transcription of at least 45 genes is directly controlled by the McbR repressor. These 45 genes encode a variety of functions in (S-adenosyl)methionine and cysteine biosynthesis, in sulphate reduction, in uptake and utilization of sulphur-containing compounds and in transcriptional regulation. The function of the inverted repeat motif as potential McbR binding site in front of the geneshom,cysI,cysK,metKandmcbRwas verified experimentally by competitive electrophoretic mobility shift analysis. A systematic search for the potential effector substance modulating the function of McbR revealed that onlyS-adenosylhomocysteine prevented the binding of McbR to its target sequence. These results indicate that the transcriptional repressor McbR directly regulates a set of genes comprising all aspects of transport and metabolism of the macroelement sulphur inC. glutamicum. As the activity of McbR is modulated byS-adenosylhomocysteine, a major product of transmethylation reactions, the results point also to a novel regulatory mechanism in bacteria to control the biosynthesis ofS-adenosylmethionine. [ABSTRACT FROM AUTHOR]