The recent convergence of chiral molecules with metal halide perovskite frameworks gives rise to an interesting family of chiral systems: two-dimensional, chiral hybrid organic–inorganic perovskites (chiral-HOIPs). While possessing photovoltaic properties of traditional HOIPs, this class of materials is endowed with chirality through its organic ligands in which the degeneracy of the electron spin in charge transport is broken. That is, the chirality-induced spin selectivity (CISS) effect manifests, making it a promising platform to bridge opto-spintronic studies and the CISS effect. In this work, chiral-HOIP/NiFe heterostructures are studied by means of the magneto-optical Kerr effect using a Sagnac interferometer. Upon illumination of the chiral-HOIPs, the Kerr signal at the chiral-HOIP/NiFe interface changes, and a linear dependence of the response on the magnetic field is observed. The sign of the slope was found to depend on the chirality of the HOIPs. The results demonstrate the utility of chiral-HOIP materials for chiral opto-spintronic applications.

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Solution‐processed metal halide perovskite (MHP) single crystals (SCs) are in high demand for a growing number of printed electronic applications due to their superior optoelectronic properties compared to polycrystalline thin films. There is an urgent need to make SC fabrication facile, scalable, and compatible with the printed electronic manufacturing infrastructure. Here, a universal cosolvent evaporation (CSE) strategy is presented by which perovskite SCs and arrays are produced directly on substrates via printing and coating methods within minutes at room temperature from drying droplets. The CSE strategy successfully guides the supersaturation via controlled drying of droplets to suppress all crystallization pathways but one, and is shown to produce SCs of a wide variety of 3D, 2D, and mixed‐cation/halide perovskites with consistency. This approach works with commonly used precursors and solvents, making it universal. Importantly, the SC consumes the precursor in the droplet, which enables the large‐scale fabrication of SC arrays with minimal residue. Direct on‐chip fabrication of 3D and 2D perovskite photodetector devices with outstanding performance is demonstrated. The approach shows that any MHP SC can now be manufactured on substrates using precision printing and scalable, high‐throughput coating methods.

this regard, semiconductor-based gammaray detectors are especially appealing due to their high sensitivity and excellent detection efficiency. The high-purity germanium (HPGe) detectors can offer ultrahigh energy resolution (≈0.3% for 662 keV gamma-ray). However, HPGe detectors need to work at cryogenic temperature, which requires complicated cooling accessories and thus affects their wide deployment in many applications. [4,5] Cadmium zinc telluride (CdZnTe) is one of the leading semiconductor detector materials for room-temperature gamma-ray detection, thanks to its suitable bandgap energy of 1.57 eV and exceptional charge carrier transport properties. Nevertheless, CdZnTe often suffers from materials issues, for example, Te inclusions/ precipitates and subgrain boundaries, which originate from the high temperature melt growth and subsequent cooling processes. [6] Consequently, the high manufacturing cost of detector-grade CdZnTe, mainly due to low yield of as-grown ingots and need of essential post-growth thermal treatment, still limits their large-scale deployment. Another compound semiconductor material, thallium bromide (TlBr), could exhibit interesting room-temperature gamma-ray detection capabilities initially. Nevertheless, the associated polarization phenomenon, where the detection performance degrades over time, presents a realistic challenge toward the use of TlBr for gamma-ray detection. As a result, there is a strong need to search for new gamma-ray detector materials with attractive device performance and competitive fabrication cost.In recent years, perovskite materials have emerged as new promising materials for ionizing radiation detection due to their unique advantages, such as suitable bandgap energy, high average atomic number Z, high resistivity, large mobility-lifetime product, and low cost using solution growth methods. [1,7,2,3,8] In 2016, Yakunin et al. first demonstrated that the solution-grown formamidinium (FA)-based hybrid lead halide perovskites, FAPbI 3 , could achieve radiation response to gamma photons. [8] In 2017, Wei et al. reported the energyresolving gamma spectrum of Cs-137 isotope using alloyed hybrid perovskites CH 3 NH 3 PbBr 2.94 Cl 0.06 single crystals (SCs). [9] It should be noted that hybrid-perovskites-based devices often face the performance instability issue, which is mainly caused Lead halide perovskites have recently attracted intensive attention as competitive alternative candidates of legacy compound materials CdTe, CdZnTe, and TlBr for high sensitivity energy-resolving gamma-ray detection at room temperature. However, the use of lead in these lead halide perovskites, which is necessary for increasing the stopping power of gamma radiation, poses a serious environmental concern due to the high toxicity of lead. In this regard, environmental-friendly perovskite-based gamma-ray detector materials with key energy-resolving capabilities are highly desired. Here, the gamma energy-resolving performance of a new class of all-inorganic and lead-free Cs 2 AgBiBr 6 doubl...

The dimerization of monomeric beryllium species was studied via density functional theory (DFT) calculations, and the influences of deprotonation and substitution with various halide anions on the polymerization were explored. The results indicate that the dimerization was accomplished by aggregation followed by a nucleophilic attack reaction, and the hydrolysis that provides the nucleophilic hydroxyl group is a prerequisite for polymerization. An activation energy of 49.7 kJ mol(-1) and an aggregation energy of -52.2 kJ mol(-1) were found for the formation of Be2(OH)(H2O)6 (3+), indicating a exothermic reaction. Deprotonation promotes aggregation and increases the energy barrier to activation. Replacing a bound water with an F(-) anion makes aggregation more thermodynamically favorable, but it does not significantly change the energy barrier. It was concluded that the charge and electronegativity of the anion are crucial influences on the energy of the activation barrier, whereas the aggregation energy is influenced not only by the charge but also by the symmetry of the bridging structure in the aggregate.