Mn(II)-Doped Perovskites with Carboxylic Acid Dimers Exhibiting Scintillation

Layered hybrid metal halide perovskites, characterized by their distinctive quantum well structures and significant exciton binding energies, exhibit exceptional fluorescence properties, rendering them ideal candidates for high light yield scintillators. However, significant challenges remain in synthesizing layered metal halide perovskites with high photoluminescence quantum yields (PLQY), large Stokes shifts, and stable radioluminescence (RL). In this study, a stable Mn(II)-doped layered perovskite was successfully synthesized. Structural rigidity is largely enhanced by the unique carboxylic acid dimers, as a result reducing nonradiative recombination induced by the stretching vibration. Mn(II) doping into (HOOC₆H₁₀NH₃)₂PbBr₄ allows for efficient energy transfer, which optimizes luminescence performance. The effects of self-absorption are almost eliminated by the significant Stokes shift induced by this doping. The distinctive ⁴T_1g-⁶A_1g transition induces a pronounced orange-red emission at 613 nm, with the PLQY significantly increasing from 14.76% to 64.24%. Additionally, the scintillator demonstrates an outstanding light yield of 28,600 photons/MeV and a low detection limit of 100.8 nGy_air/s, maintaining exceptional stability under continuous X-ray exposure. These properties render it ideal candidates for applications in luminescent devices and scintillators.