Improving the Scintillation Performance of PEA2PbBr4 Through Zn2+ and Sb3+ Interstitial Doping Strategy

Organic-inorganic halide 2D perovskite single crystals have recently emerged as promising scintillators for gamma (γ) rays and fast neutrons (nf) detection. However, their energy resolution in γ-rays detection still significantly lags behind that of perovskite semiconductor detectors. Improving crystal defects and enhancing light yield to optimize light output detected by the photomultiplier tube are crucial strategies for addressing this issue. Herein, it is demonstrated that Zn2+ and Sb3+ cation interstitial doping strategy can effectively reduce internal defects within the phenylethylammonium lead bromide (PEA2PbBr4) crystal by regulating lattice expansion. This approach also suppresses light loss caused by exciton-exciton annihilation and accelerates electron-hole recombination processes, optimizing both the luminescence intensity and decay lifetime of the scintillator. The Zn2+ and Sb3+ doping PEA2PbBr4 scintillator achieve an optimal energy resolution of 4.84% and 5.65% at 662 keV for the photopeak, respectively. Additionally, in the 241Am-Be field, effective identification of nf and γ-rays around 1100 keVee is achieved using a pulse shape discrimination (PSD) method, with the figure of merit (FOM) being 0.85 and 1.03, respectively. This work provides a reliable new approach for optimizing the scintillation performance of 2D perovskite and promotes the application of 2D perovskite scintillator in γ-rays and nf detection.