Host-induced Mn2+ coordination for multicolor emission and high-resolution X-ray detection in metal halide perovskites

Mn2+ doping provides an effective approach to modulate the photoluminescence (PL)and X-ray scintillation properties of metal halide perovskites (MHPs); however, strategies to achieve customizable luminescence through structural design remain challenging. Here, 1D CsCdBr3, 1D/0D Cs7Cd3Br13, and 0D Cs3CdBr5 hosts were precisely synthesized via reactant ratio control. The different host structures were designed to induce distinct Mn2+ coordination environments, resulting in structure-dependent red, yellow, and green emission. The effects of Mn2+ incorporation on the photoluminescence and X-ray scintillation of different hosts were systematically studied through combined experimental and theoretical approaches. Warm white light-emitting diode (LED) fabricated from a mixture of the three compounds exhibited high color rendering (Ra = 91.4), a correlated color temperature of 4201 K, and CIE coordinates of (0.37, 0.38), demonstrating high-performance solid-state lighting. Flexible scintillator films embedded in a polydimethylsiloxane (PDMS) matrix showed excellent radioluminescence stability and high spatial resolution under X-ray irradiation. Notably, CsCdBr3:Mn displayed superior X-ray imaging performance (23.6 lp/mm) due to its high atomic packing factor and density. This work establishes a host structure guided strategy for constructing specific Mn polyhedra, offering a promising approach to developing multifunctional, high-performance solid-state lighting and flexible X-ray scintillator materials.