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Perovskite solar cells (PSCs) based on formamidinium lead iodide (FAPbI3) have demonstrated the highest power conversion efficiencies. Typically fabricated through solution‐processing, FAPbI3 films necessitate intricate crystallization control to avoid the formation of a more stable non‐perovskite phase. Magnetron sputtering, an effective solvent‐free technique, has gained attention for producing large‐area perovskite films. Here, a novel approach to create high‐quality FAPbI3‐based perovskite thin films by employing magnetron sputtering is presented. Specifically, a mechanosynthesized blend of (FA1‐xMAx)Pb(I1‐xBrx)3 (MA = methylammonium) is used as a single‐source target for sputtering, and a post‐annealing transforms various phases in the initial deposited film into coherent FAPbI3‐based films with an ultra‐long and controlled crystallization process. Despite minimal residual MABr after post‐annealing, its presence is crucial in the formation of perovskite film, as evidenced by a distinct solid‐state phase transformation process is presented. A comprehensive investigation of the films' structural, compositional, and optical properties, with respect to varying MABr doping ratios, reveals details of perovskite phase development and the pivotal influence of MABr. PSCs fabricated with the optimized films display a substantial increase in the power conversion efficiency, reaching 20.1%. These results underscore the potential of combining magnetron sputtering and post‐annealing in the scalable production of high‐efficiency PSCs. [ABSTRACT FROM AUTHOR]

The dual emission (DE) characteristics of atomically precise copper nanoclusters (Cu NCs) are of significant theoretical and practical interest. Despite this, the underlying mechanism driving DE in Cu NCs remains elusive, primarily due to the complexities of excited state processes. Herein, a novel [Cu4(PPh3)4(C≡C−p−NH2C6H4)3]PF6 (Cu4) NC, shielded by alkynyl and exhibiting DE, was synthesized. Hydrostatic pressure was applied to Cu4, for the first time, to investigate the mechanism of DE. With increasing pressure, the higher‐energy emission peak of Cu4 gradually disappeared, leaving the lower‐energy emission peak as the dominant emission. Additionally, the Cu4 crystal exhibited notable piezochromism transitioning from cyan to orange. Angle‐dispersive synchrotron X‐ray diffraction results revealed that the reduced inter‐cluster distances under pressure brought the peripheral ligands closer, leading to the formation of new C−H⋅⋅⋅N and N−H⋅⋅⋅N hydrogen bonds in Cu4. It is proposed that these strengthened hydrogen bond interactions limit the ligands′ vibration, resulting in the vanishing of the higher‐energy peak. In situ high‐pressure Raman and vibrationally resolved emission spectra demonstrated that the benzene ring C=C stretching vibration is the structural source of the DE in Cu4. [ABSTRACT FROM AUTHOR]

Pleurotus tuoliensis is a unique species discovered in Xinjiang, China, which is recognized for its significant edible, medicinal, and economic value. It has been successfully incorporated into industrial production. Controversy has emerged concerning the evolution and environmental adaptability of this species due to inadequate interspecific ecology and molecular data. This study examines the germplasm resources of P. tuoliensis in the Xinjiang region. A total of 225 wild and cultivated strains of P. tuoliensis were gathered from seven representative regions. Phylogenetic analysis revealed that seven populations were notably segregated into three distinct groups, primarily attributed to environmental factors as the underlying cause for this differentiation. Population historical size data indicate that P. tuoliensis underwent two expansion events, one between 2 and 0.9 Mya (Miocene) and the other between 15 and 4 Mya (Early Pleistocene). The ancient climate fluctuations in the Xinjiang region might have contributed to the comparatively modest population size during the Pliocene epoch. Moreover, through the integration of biogeography and ancestral state reconstruction, it was determined that group C of P. tuoliensis emerged initially and subsequently dispersed to groups D and B, in that order. Subsequently, group D underwent independent evolution, whereas group B continued to diversify into groups A and EFG. The primary factor influencing this mode of transmission route is related to the geographical conditions and prevailing wind direction of each group. Subsequent research endeavors focused on assessing the domestication adaptability of P. tuoliensis to different substrates. It was found that the metabolic processes adapted during the domestication process were mainly related to energy metabolism, DNA repair, and environmental adaptability. Processes adapted to the host adaptability include responses to the host (meiosis, cell cycle, etc.) and stress in the growth environment (cysteine and methionine metabolism, sulfur metabolism, etc.). This study analyzed the systematic evolution and genetic differentiation of P. tuoliensis in Xinjiang. The identified loci and genes provide a theoretical basis for the subsequent improvement of germplasm resources and conducting molecular breeding. [ABSTRACT FROM AUTHOR]

The stereochemical expression of the 6s2 lone pair on the lead atom has a significant impact on the crystal structures and physical properties of lead halide perovskites. Two-dimensional (2D) lead bromide perovskites often exhibit a broadband emission, yet the structural origin of the broadband emission has been under debate. Here, we report the synthesis and characterization of a 2D lead bromide hybrid (4-chlorophenylammonium)2PbBr4 that consists of a combination of the octahedral unit PbBr6 and the rarely observed capped octahedral unit PbBr7 through corner-sharing and edge-sharing linkages. The seven-coordination geometry indicates a strong stereo-active lone pair on the Pb2+ cation. By comparing this structure with two representative 2D perovskites, (benzylammonium)2PbBr4 and (4-aminotetrahydropyran)2PbBr4, we establish how the lone pair expression affects the local coordination geometry of the Pb2+ cation and the resulting optical and electronic properties. As the Pb–Br bond length increases, the lone pair expression leads to off-centering displacement of Pb2+ within the octahedra and then the formation of seven-coordination capped octahedra. Density functional theory calculations indicate that the off-centering distorted octahedra and capped octahedra are due to the asymmetric distribution of the Pb electrons that have both s and p orbital characteristics. Spectroscopic studies show the photoluminescence spectra evolving from narrowband emission to broadband emission with increasing LPE, as well as softer and more anharmonic lattice vibrations that facilitate exciton self-trapping. Our results demonstrate that lone pairs could be a powerful design rule for developing light emitting materials. [ABSTRACT FROM AUTHOR]