Green synthesis of a manganese-based anti-perovskite with anti-thermal quenching properties for LEDs

Abstract

Due to their excellent properties, lead halide perovskites are promising candidates for future optical emitters. However, lead (Pb) toxicity in perovskite materials poses a critical concern for their commercial application in optoelectronic devices. Herein, we present a facile and environmentally friendly approach for synthesizing lead-free [MnBr₄]BrCs₃ perovskite materials. Our approach involves using a water-based evaporation crystallization technique to prepare [MnBr₄]BrCs₃ with an anti-perovskite structure. The anti-perovskite structure of the powder was confirmed through X-ray diffraction analysis. The prepared fluorescent powder exhibited strong green emission with a peak emission wavelength of 524 nm and an extremely narrow bandwidth (∼41 nm). Variable-temperature steady-state luminescence spectroscopy was used to investigate the temperature-dependent photophysical properties of [MnBr₄]BrCs₃, which reveal notable thermal stability and anti-thermal quenching behavior, making them potential candidates for light-emitting diodes (LEDs). The temperature-dependent emission behavior was further investigated using temperature-dependent XRD, lifetime analysis, magnetic measurements, and first-principles calculations, suggesting that lattice expansion and Mn-related interactions may influence the excited-state dynamics and reduce energy-migration-related quenching losses. As proof, a phosphor-converted UV LED based on the material was successfully prepared, exhibiting a high maximum brightness (257 445 cd m⁻²) and a long half-life (870 min). These findings have significant implications for developing efficient and environmentally friendly perovskite-based opto-electronics.