Efficient and stable inorganic lead-free halide perovskites have attracted tremendous attention for next-generation solid-state lighting. However, single perovskite phosphors with strong, tunablecolor-temperature white-light emission are rare. Here, a doping strategy was developed to incorporate Sb 3+ and Bi 3+ ions into Cs 2 NaInCl 6 single crystals. Blue and yellow emission for white light with a 77% quantum yield was observed. The dual-emission originates from different [SbCl 6 ] 3− octahedron-related self-trapped excitons (STEs). The blue emission is attributable to limited Jahn−Teller deformation from Sb 3+ doping. Largeradii Bi 3+ increase the deformation level of the [SbCl 6 ] 3− octahedron, enhancing yellow STE emission. Density functional theory calculations indicated that the Bi 3+ doping forms a sub-band level, which produces yellow STE emission. Tuning between warm and cold white light can be realized by changing the Sb 3+ /Bi 3+ doping ratio, which suggests a unique interaction mechanism between Sb 3+ and Bi 3+ dopants, as well as Bi 3+ -induced lattice distortion in double perovskites.

The simplest facet‐shell formulation involves the combination of the constant‐strain membrane triangle with a constant‐curvature bending triangle. The paper first describes an alternative co‐rotational procedure to the one initially proposed by Peng and Crisfield in 1992. This new formulation introduces a spin matrix which allows a simpler formulation for the consistent tangent stiffness matrix. The paper then moves to the dynamics of the element. To obtain stable solutions, an energy‐conserving mid‐point time‐integration scheme is developed. This scheme exactly conserves the total energy when external forces are constant and when the physical system does not present any damping. The performance of this scheme is compared with other more conventional implicit schemes through a set of numerical examples involving large‐scale rotations.

Metal halide perovskites are promising optoelectronic materials due to their unique luminescent properties. However, their practical application is limited by their poor chemical stability, especially in humid environments. Moisture can cause phase changes or chemical decomposition, resulting in significant fluorescence quenching. In this study, a copper‐based organic–inorganic hybrid metal halide (t‐BA)3Cu6I9 is synthesized (t‐BA+ is the tert‐butyl‐ammonium ion (C(CH3)3NH3+)). This material exhibits water‐induced luminescence, and its chemical stability in humid environments is being investigated. Tetragonal t‐BA3Cu6I9 is not luminescent, but it reacts quickly with water in the air. The resultant (t‐BA)2Cu2I4·H2O has a broad green emission peak at 520 nm, high photoluminescence quantum yield of 59.4%. Remarkably, (t‐BA)2Cu2I4·H2O is converted back to t‐BA3Cu6I9 at temperatures above 40 °C. This phase conversion is highly repeatable, and the luminescent intensity can be fully recovered after 50 transformation cycles. The mechanism of luminescence is investigated through temperature‐dependent photoluminescence spectra and theoretical calculation, which suggests that (t‐BA)2Cu2I4·H2O has a more localized charge distribution and sufficient polyhedral distortion, resulting in a bright and efficient emission from self‐trapped excitons. This is the first report of water‐induced luminescence in copper‐based metal halides, and it paves the way for stable luminescent materials that are responsive to humidity.

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All‐inorganic cesium lead bromide perovskites have attracted a lot of attention because of their excellent optical properties that can potentially be applied in various optical devices. However, large‐scale preparation of cesium lead bromide perovskites with outstanding optical performance is still hindered by the poor solubility of CsBr in polar aprotic solvents. In this work, a water/dimethylsulfoxide (DMSO)/dimethylformamide (DMF) system is demonstrated for the synthesis of inorganic cesium lead bromide perovskites, where the introduction of water can effectively address the dissolution issue of Cs+ ions. Large‐scale synthesis of pure‐phase emissive Cs4PbBr6 with a product yield of up to 73% is achieved and the photoluminescence quantum yield of resulting product reaches as high as 76%. The origin of the light emission is further revealed by the photoluminescence evolution of the colored Cs4PbBr6 single crystals. Furthermore, reversible phase transitions between Cs4PbBr6, CsPbBr3 and CsPb2Br5 are achieved by changing solely the water content, which paves the way for the recycle of the mother solution of Cs4PbBr6 without generation of additional hazardous waste. The three‐solvent‐based synthetic approaches enable an economical, robust, and large‐scale production for all‐inorganic cesium lead bromide perovskites.