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Metal halide CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) have been widely studied because of their high photoluminescent quantum yield (PLQY) and tunable emission wavelength. However, their weak hydrothermal stability greatly limits the use of CsPbX3 NCs under harsh conditions. This work successfully solved the problem of poor stability of CsPbX3 NCs through the ethylene vinyl acetate (EVA) film coating strategy and expanded the application range of CsPbX3 NCs. In addition, we demonstrated an improved Yb-doped hot injection strategy, successfully prepared a Yb-doped CsPbBrI2 NC in EVA composite film (CsPbBrI2 NCs/ECF), and improved the PLQY of the prepared CsPbBrI2 NCs/ECF. Furthermore, this work studied the application of CsPbX3 NCs/ECF in the field of backlight displays. The results show that CsPbX3 NCs/ECF has a wide color gamut, which reaches 119.9% of the National Television Standards Committee 1953 standard color gamut and 89.2% of the Rec. 2020 standard color gamut. [ABSTRACT FROM AUTHOR]

In recent years, silicon (Si) photodetectors (PDs) have been widely used in daily life, but the ultraviolet (UV) region response is extremely low, while perovskite nanocrystals (NCs) can be used as a light conversion layer to effectively improve the UV region detection performance due to their high absorption coefficient. At the same time, embedding NCs into a glass matrix can protect NCs from the adverse external environment, which can greatly prolong the effective working time of the detector. In this work, a series of perovskite NC glasses (PNGs) with intrinsic emission but still maintaining high transmittance were fabricated successfully by regulating the concentration of CsPbCl2Br1 NCs. Furthermore, the rare-earth ion Tb3+ was successfully introduced into CsPbCl2Br1 NCs, achieving energy transfer of the exciton to Tb3+, and the photoluminescence quantum yield (PLQY) had a big boost from 11.1 to 28.1%. In the end, the prepared CsPbCl2Br1:Tb3+ PNG was first integrated with Si PDs, and the UV responsibility of Si PDs was enhanced due to the absorption of CsPbCl2Br1 PNG doped with Tb3+ in the UV region. At 320 nm, the responsivity of Tb3+-doped CsPbCl2Br1 PG-Si PDs is significantly higher than that of bare Si PDs. In addition, CsPbCl2Br1:Tb3+ PNG-Si PDs maintained excellent photocurrent stability. The CsPbCl2Br1:Tb3+ PNGs are expected to be one of the optimum semiconductor materials for next-generation high-performance UV PDs. [ABSTRACT FROM AUTHOR]

All-inorganic CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) are the most promising next generation photoelectric materials owing to their excellent properties. Although embedding perovskite NCs into a glass matrix improves their stability, different applications require perovskite nanocrystal glasses (PNGs) with different properties. In this work, we controlled the network structure of the precursor glass by changing the content of ZnO (3.8–11.4 mol. %) in the raw materials, thus inhibiting the direct precipitation of CsPbCl2Br NCs in the glass (i.e., the self-crystallization process), and obtained samples with local emission and high transmittance. In addition, we incorporated rare-earth (RE) Yb3+ into a CsPbCl2Br PNG to achieve efficient ultraviolet (UV) to near-infrared quantum cutting emissions and boost the UV response of silicon photodetectors (PDs). Finally, after combining the Yb3+-doped CsPbCl2Br PNG on the Si PDs, the responsivity of the latter increased to 0.014 A/W at 320 nm, which is 14 times higher than that of the bare Si PDs. Moreover, Si PDs based on Yb3+-doped CsPbCl2Br PNG exhibited excellent photocurrent stability. [ABSTRACT FROM AUTHOR]

As a promising optoelectronic material, all-inorganic perovskite nanocrystals (NCs) have attracted much attention, but there are few studies on zero-dimensional Cs4PbBr6 perovskite NCs. Herein, the in situ growth of the CsPbBr3/Cs4PbBr6 NCs inside amorphous glass has been achieved by adjusting the ratios of Cs2CO3 and PbBr2. The effect of different proportions with raw materials on the phase, microstructure, and photoluminescence (PL) characteristics was discussed in detail. Moreover, CsPbBr3/Cs4PbBr6 NCs glass with high photoluminescence quantum yield (PLQY) of ∼58.9% was obtained by optimizing the heat treatment condition. In particular, CsPbBr3/Cs4PbBr6 NCs glass realizes low-threshold amplified spontaneous emission (ASE) at room temperature. Meanwhile, as a green light source, CsPbBr3/Cs4PbBr6 NCs glass makes white light-emitting diode (WLED) presents a wide color gamut. Importantly, CsPbBr3/Cs4PbBr6 NCs glass displays excellent water/thermal stability. All these results prove that CsPbBr3/Cs4PbBr6 NCs glass has broad application prospects in the field of lasers and backlight displays. [ABSTRACT FROM AUTHOR]

Currently, high optical purity, perfect stability, and high photoluminescence quantum yield (PLQY) are very important, being the key to obtain high‐quality luminescent materials. The research of perovskite nanocrystals (NCs) as optical materials is in full swing. Nevertheless, the low PLQY value, especially for the red‐emitting perovskite NCs, is a main obstacle to applications in display. This work reports the optimized components to synthesize CsPb(Br/I)3 NCs glasses whose PLQY achieves a big boost from 15.4% to ≈60% for the first time. Furthermore, the specimens exhibit exceptional tolerance to water and thermal and hence contribute to applicability in high‐performance light‐emitting diode (LED) and 3D printing. By combining CsPb(Br/I)3 NCs glass powder and yttrium aluminum garnet (YAG):Ce phosphor with blue chips, the assembled white LEDs reach a high luminous efficiency at 113.0 lm W−1. The resulting high PLQY is to the benefit of a substantial step toward the practical application of inorganic perovskite materials in the fields of optoelectronic devices and additive manufacturing. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries have attracted increasing attention for next-generation energy storage systems due to their high energy density and abundance of potassium. However, the lack of suitable anode highly hampers its practical application due to the large ionic radius of K + . Herein, a Se 3 P 4 @mesoporous carbon (Se 3 P 4 @C) composite is reported as a high-performance anode for potassium-ion batteries. The Se 3 P 4 @C composite is synthesized through an in situ combination reaction between red phosphorus and Se within a porous carbon matrix. In this way, the nano-sized Se 3 P 4 is well confined in the porous carbon and thus exhibits a close contact with the carbon matrix. This can significantly improve the conductivity and alleviate the volume change during the cycling process. As a result, the Se 3 P 4 @C exhibits a high reversible initial capacity of 1036.8 mAh g -1 at a current density of 50 mA g -1 as well as an excellent cycle performance with a capacity decay of 0.07% per cycle over 300 cycles under 1000 mA g -1 . In terms of high specific capacity and stable cycling performance, the Se 3 P 4 @C anode is a promising candidate for advanced potassium-ion batteries., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)