Tb-doped MA0.89FA0.11PbBr3 perovskite single crystals for gamma-ray detection

Abstract

Rare-earth doping has emerged as a promising strategy to tailor the optoelectronic properties of metal halide perovskites, yet its potential for enhancing gamma-ray detection performance remains underexplored. The synthesis of large-sized, rare-earth doped perovskite single crystals remains challenging due to the adverse effects of dopants on crystal growth and lattice stability. Herein, we achieved 16 mm sized MA_0.89FA_0.11PbBr₃:Tb single crystals (Tb/Pb = 0.13–0.67%) via nucleation control and precursor regulation. The X-ray fluorescence mapping confirms the uniform distribution of Tb³⁺ within the crystal lattice at a low Tb/Pb ratio (≤0.35%). The successful incorporation of rare earth ions and a concomitant lattice contraction profoundly enhance the charge transport characteristics. Specifically, doping with 0.13% Tb³⁺ increased the carrier mobility from 55 to 154 cm² V⁻¹ s⁻¹ and prolonged the carrier lifetime from 197 to 4422 ns. Consequently, the fabricated gamma-ray detector achieved a high energy resolution of 4.3% for ²⁴¹Am radiation (59.5 keV), a significant improvement over 15.7%. This work demonstrates rare-earth doping as an effective strategy toward high-performance perovskite radiation sensors.