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Ultra-stable CsMnX3 nanocrystals embedded glasses with bright and broad red photoluminescence (PL) emission at 649 nm were synthesized as an excellent red phosphor for white light-emitting diode (LED) devices with a high color rendering index (CRI).

The 4.2 nm α-CsPbI3 quantum dots - polymer composite films with 630 nm emission and high stability have been achieved, which are used for LED displays with color gamut to 96% of the Rec. 2020 standard.

Manganese doped perovskite nanocrystals (NCs) have been synthesized by a novel two-step hot injection strategy with an unprecedented Mn doping efficiency of 48.5%, bright orange emission under ultraviolet light and X-ray excitation and a photoluminesce (PL) quantum yield of 84.4%, making them excellent luminescent materials.

A novel quaternary ammonium antinomy halide was synthesized and used to construct bright orange LEDs with a luminous efficiency of 24.5 lm W−1, which can run continuously in air for more than 1200 minutes without performance degradation.

In recent years, two-dimensional (2D) layered tin halide perovskites have attracted much attention due to their excellent luminescence properties compared with their three-dimensional (3D) analogs. Here, we synthesized 2D perovskites of the form (RNH3)2SnBr4 through a facile hot-injection approach without the use of toxic tri-n-octylphosphine (TOP) as the solvent. We found that these compounds have strong photoluminescence (PL) emission with high PL quantum yields (QY) of 35% ((C6H13NH3)2SnBr4), 82% ((C8H17NH3)2SnBr4), 60% ((C12H25NH3)2SnBr4) and 50% ((C18H35NH3)2SnBr4). Among them, ((C6H13NH3)2SnBr4) was synthesized for the first time; however, (C18H36NH3)2SnBr4 perovskites showed the best stability with a PL QY decrease of less than 1% after 30 days under ambient air and humidity conditions. In addition, other 2D (C8H17NH3)2SnX4 (X = Br, I, or mixture) perovskites were prepared by adjusting the halide ratio, resulting in spectral tunability from yellow to red. Interestingly, through Zn2+ doping, the morphology became more uniform, and the PL stability was significantly improved. Finally, we used Zn2+-doped (C8H17NH3)2SnBr4 yellow phosphor to fabricate UV-pumped yellow LEDs. We expect these 2D perovskites to be promising phosphors in future solid-state lighting and display technologies.

Recently, two-dimensional (2D) metal halide perovskite materials with wide application in perovskite-based solar cells have attracted significant attention. Among them, 2D mixed lead–tin perovskites have not been systematically explored. Herein, we synthesize a 2D phenethylammonium (PEA) tin–lead bromide perovskite, PEA2SnxPb1−xBr4, via a simple solution-phase approach without toxic reagents and high temperatures. By tuning the ratio of Sn and Pb, the UV-vis absorption spectra showed unique bandgap bending behaviors. DFT calculations indicate the key effects of spin–orbital coupling (SOC) without the interference of lattice distortion. Moreover, we provided the standard equation with a correction term to introduce the influence of SOC. These results not only provide a step forward towards the bandgap engineering of perovskites, but also help to expand the application of 2D perovskite materials.

This communication describes a facile hot-injection method for the synthesis of novel micrometer-size formamidinium lead bromide perovskite (FAPbBr3) nanosheets of monolayer thickness (around 2.4 nm). Due to the strong quantum confinement effect, the as-synthesized large-sized perovskite nanosheets displayed an unprecedented extremely blue-shifted first sharp excitonic absorption peak at 435 nm and an emission peak at 437 nm, as compared to that of bulk FAPbBr3 crystals at 551 nm.