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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]

The perovskite material has received much attention due to its excellent photoelectric properties. However, the toxicity of Pb has always affected the wide application of perovskite materials. Herein, we proposed to replace Pb ions with the same divalent ions Ba and dope them into the CsPbBr3 perovskite nanocrystals' (PNCs) lattice to reduce the content of Pb elements. In this work, we have successfully prepared a series of CsPb1−xBaxBr3 PNCs (x = 0, 0.1, 0.2, 0.3, and 0.4) and CsPbBr3 PNCs (Ba-doped concentration = x = 0, 0.05, 0.10, 0.15, and 0.20); the best among them were CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs, respectively. Compared with CsPbBr3 PNCs, the photoluminescence (PL) intensity of CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs has been improved to different degrees. It was worth mentioning that after the addition of a Ba element, the photoluminescent quantum yield (PLQY) of CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs was increased to 81% and 65%, respectively. It was due to the high PLQY of CsPb0.7Ba0.3Br3 PNCs that the selected CIE color coordinate monochromatic light encompassed 119.0% of NTSC color gamut. [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]

Perovskite nanomaterials have attracted significant attention in the field of nanoscale laser field, however, poor environmental stability is the biggest challenge that restricts their applications. In this study, an in situ synthesis method was used to encapsulate CsPbBr3 nanocrystals (NCs) in titanium silicalite molecular sieve (TS-1). Owing to the hollow structure and the hydrophobicity of the TS-1, the hydro and thermal stabilities of the perovskite NCs were significantly improved. Using AB glue, we prepared thin films using a one-step spin coating method, and synthesized highly compact and smooth CsPbBr3 nanocomposite thin films. Amplified spontaneous emission (ASE) was achieved with a low-threshold under two-photon excitation at room temperature, and a stable emission under continuous intense laser shots in an ambient atmosphere was maintained. The influence of the perovskite concentration and calcination temperature on the ASE threshold was also investigated. This study will significantly broaden the application of perovskite nanocrystals in practical nonlinear optical devices. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite (CsPbX3, X = Cl, Br, I) nanocrystals (NCs) with promising optical properties are recognized as a rising star among photoelectric materials, but their inevitable instabilities limit extensive application. Herein, a new one‐step strategy for encapsulating CsPbX3 NCs with porous zeolite via the hot injection method is explored. By altering the mole ratio of PbX2, the emission wavelength of CsPbX3@zeolite is found to be regularly modulated from blue‐emission (CsPbCl2Br@zeolite, 436 nm) to red‐emission (CsPbBrI2@zeolite, 648 nm), thus enabling full spectrum adjustment. Due to the surface passivation of zeolite to CsPbX3 NCs, CsPbX3@zeolite possess an outstanding quantum yield and display excellent thermal/photo/air stability. Subsequently, white light‐emitting diodes based on green‐CsPbBr3@zeolite and red‐CsPbBrI2@zeolite are constructed and applied to the backlit display, achieving a wide color gamut of 134.2% for NTSC 1953 and 99.8% for Rec. 2020. The CsPbX3@zeolite implanted with a polymethyl methacrylate film is used to realize upconversion emission under an 800 nm laser at room temperature. Furthermore, amplified spontaneous radiation based on CsPbBr3@zeolite films is achieved. These results convincingly indicate broad application prospects for CsPbX3@zeolite prepared via this simple method. [ABSTRACT FROM AUTHOR]