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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 order to achieve high color rendering index (CRI) and low correlated color temperature (CCT) indoor lighting, single component phosphors with broadband dual emission emission are high demanded for white light emitting diodes (WLEDs). However, phosphors with such fluorescent properties are rare at present. Herein, we report a facile solid-state chemical method for the synthesis of single-component phosphor with broadband emission and large Stokes shift that can meet the requirements of future white light sources. These new tetrabutylammonium copper halides phosphors have excellent warm white emission characteristics, and their luminescence peaks located at 494 nm and 654 nm, respectively. The optimized photoluminescence (PL) quantum yield can reach 93.7%. The typical CIE coordinate of the as-fabricated WLED is at (0.3620, 0.3731) with CRI of 89 and low CCT of 4516 K.

Precise, sensitive, and reversible thermochromic luminescent sensing can be achieved by PEAMnBrxI3−x (x = 0/1/2/3). Their luminescence ratios of green to red exhibited a reversible linear response to the temperature increment process (from 40 °C to 120 °C), bright luminescence under high temperature, and reversible heating–cooling circulation performance. Based on the thermochromic luminescence properties, the PEAMnBr2I–polymer film was used for precise and real-time temperature sensing. A deep understanding of their thermochromic luminescence mechanism can facilitate the design of thermochromic materials with high performance and their wider applications.

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.

Perovskite-based light-emitting diodes (PeLEDs) are arousing great interest as promising technology for next-generation displays due to their narrow emission linewidth, tunable emission wavelength, and high photoluminescence quantum yield. Due to the superiorities of the simple fabricating process and high efficiency, the in situ preparation of PeLEDs has attracted more attention. However, numerous defects are induced due to the ligand loss in the in situ fabrication of the perovskite film, which restricts the performance improvement of PeLEDs to a larger extent. Here, we introduce a dual ligand 2,2-diphenylethylamine bromide (DPEA-Br) in precursor solution and n-octylphosphonic acid (OPA) in antisolvent for in situ fabricating FAPbBr3 perovskite nanocrystals (PNCs). As a result, the OPA–FAPbBr3 PNC films demonstrate a higher crystallinity, a longer radiative lifetime, and an improved environmental stability, due to the synergistic effect of compensating ligands and passivating defects of OPA. Finally, we obtain a significantly enhanced device efficiency of a maximum luminance of 3273 cd m−2 and a current efficiency of 17.7 cd A−1, which are 12.5 times and 6.1 times higher than those of the control device, respectively. The ligand compensation method with OPA proposed in this work can provide a robust platform for achieving high-quality PNC films and highly efficient PeLEDs.

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 photoluminescence quantum yield of 84.4%, making them excellent luminescent materials.

Highly efficient lead halide perovskites with tunable emission performance have become new candidate materials for light‐emitting devices and displays; however, the toxicity of lead and instability of halide perovskites greatly limits their application. Herein, rapid and large‐scale synthesis of highly emissive organic–inorganic manganese halide perovskites, (C5H6N)2MnBr4 and C5H6NMnCl3, are presented by a one‐pot solution‐based method, of which (C5H6N)2MnBr4 displays a high absolute photoluminescence quantum yield (95%) in the solid‐state. The developed (C5H6N)2MnBr4 perovskite noticeably exhibits high stability. Therefore both as‐synthesized green and red emissive manganese‐based phosphors with superior optical properties are used to fabricate blue light pumped white light‐emitting diodes (WLEDs), displaying excellent quality white light with a high color rendering index value of 91 and a correlated color temperature of 5331 K. This study not only presents the robust large‐scale production synthetic approach for organic–inorganic manganese halide perovskites, but also facilitates the development of high‐performance phosphors for future lighting and display technologies.