Facile Ball-Milling Synthesis of Highly Efficient Manganese Halides Toward White Light-Emitting Display and X-Ray Imaging
Organic-inorganic hybrid Mn(II) halides have attracted considerable attention for optoelectronic applications due to their environmental friendliness and high photoluminescence quantum yield (PLQY) originating from the d-d transition (4T1(G) → 6A1) of Mn2+. However, complex synthesis processes restrict their potential for low-cost, large-scale production. In this study, the Mn(II) halide (C22H22O2P)2MnBr4 was synthesized via a simple and efficient mechanochemical ball-milling approach, achieving high photoluminescence efficiency and production yield. The halide exhibits intense green emission centered at 520 nm with a PLQY of up to 96.1%. Combined experimental and theoretical characterizations confirm that the strong light emission originates from the synergistic interaction between organic cations and inorganic framework components. A white light-emitting diode (WLED) device based on (C22H22O2P)2MnBr4 was fabricated, exhibiting bright white light emission and a wide color gamut of 113% NTSC. Furthermore, a scintillation screen based on (C22H22O2P)2MnBr4 was fabricated and utilized to investigate internal structures of various objects. The screen demonstrates a high relative light yield of 70546 photons MeV−1, a low detection limit of 33.8 nGy air s−1, and a spatial resolution of up to 12.36 lp mm−1. Finally, by integrating the scintillation screen with a thin-film transistor (TFT) backplane, the resulting X-ray detector successfully enables simulated medical imaging of dental caries. This work establishes a robust foundation for large-scale synthesis of highly efficient luminescent Mn(II) halides and highlights their potential in multifunctional light-emitting applications.