Solid-state synthesis of cesium manganese halide nanocrystals in glass with bright and broad red emission for white LEDs

Highly efficient and stable Cs3Mn0.93Zn0.07Br5@SiO2 for wide color gamut backlight displays

Mn-based perovskites have become a new candidate material for backlight display applications. However, low efficiency and poor stability are the key problems limiting the application of Mn-based perovskites. In this work, Zn-doped and SiO2-encapsulated Cs3MnBr5, denoted as Cs3Mn0.93Zn0.07Br5@SiO2 (CMZBS), was successfully synthesized to improve the photoluminescence quantum yield (PLQY) and stability. After Zn doping, the PLQY increased from 51% to 72% due to the reduction in the energy transfer between [MnBr4]2-. The PLQY can be further improved to 80% after coating SiO2. Compared with Cs3MnBr5 (CMB), CMZBS showed better stability against thermal, air, light, and polar solvents (ethanol and isopropanol). In addition, a white LED (WLED) device with a CIE of (0.323, 0.325) was fabricated by integrating CMZBS and the red phosphor K2SiF6:Mn4+ on a 465 nm blue GaN chip, which exhibited a high luminous efficiency of 92 lm W-1 and excellent stability, demonstrating its great potential application in wide color gamut displays.

A 0D hybrid lead-free halide with near-unity photoluminescence quantum yield toward multifunctional optoelectronic applications

Zero-dimensional (0D) hybrid metal halides have emerged as highly efficient luminescent materials, but integrated multifunction in a structural platform remains a significant challenge. Herein, a new hybrid 0D indium halide of (Im-BDMPA)InCl6·H2O was designed as a highly efficient luminescent emitter and X-ray scintillator toward multiple optoelectronic applications. Specifically, it displays strong broadband yellow light emission with near-unity photoluminescence quantum yield (PLQY) through Sb3+ doping, acting as a down-conversion phosphor to fabricate high-performance white light emitting diodes (WLEDs). Benefiting from the high PLQY and negligible self-absorption characteristics, this halide exhibits extraordinary X-ray scintillation performance with a high light yield of 55 320 photons per MeV, which represents a new scintillator in 0D hybrid indium halides. Further combined merits of a low detection limit (0.0853 μGyair s-1), ultra-high spatial resolution of 17.25 lp per mm and negligible afterglow time (0.48 ms) demonstrate its excellent application prospects in X-ray imaging. In addition, this 0D halide also exhibits reversible luminescence off-on switching toward tribromomethane (TBM) but fails in any other organic solvents with an ultra-low detection limit of 0.1 ppm, acting as a perfect real-time fluorescent probe to detect TBM with ultrahigh sensitivity, selectivity and repeatability. Therefore, this work highlights the multiple optoelectronic applications of 0D hybrid lead-free halides in white LEDs, X-ray scintillation, fluorescence sensors, etc.