Affiliation:
1. School of Advanced Material Engineering Kookmin University Seoul 02707 Republic of Korea
2. Department of Physics School of Applied Sciences REVA University Bangalore Karnataka 560064 India
3. Department of Chemical Engineering Kyung Hee University 1732 Deogyeong‐daero, Giheung‐gu Yongin Gyeonggi‐do 17104 Republic of Korea
Abstract
AbstractLead‐free halide perovskite‐based X‐ray scintillators with high light yield (LY) and low detection limit (LOD) have become a growing subject of research interest due to their promising application in a wide range of areas, from security to healthcare. Herein, a modified hot injection method is employed to synthesize Mn(II)‐doped Cs2NaBiCl6 double perovskite nanocrystals (DPNCs) and to examine their scintillating properties for application in X‐ray imaging and detection. The Mn(II)‐doped Cs2NaBiCl6 DPNCs exhibit a broad orange photoluminescence (PL) band at 586 nm with a PL quantum yield of 10.6%, attributed to the 4T2g(4G) → 6A1g(6S) transition of Mn2+. Temperature‐dependent PL and time‐resolved PL spectra of 4.04% Mn(II)‐doped Cs2NaBiCl6 demonstrate that the orange emission intensity initially reaches a maximum and subsequently decreases, while the decay lifetimes monotonically decrease with increasing temperature. This inconsistency can be due to the effect of the [MnCl6]4− octahedra and electron‐phonon coupling at elevated temperatures. Further, 0.05 mm thick Cs2NaBiCl6:4.04%Mn@poly(methyl methacrylate) scintillator film is synthesized with an LY of 28,350 photons MeV−1 and a LOD of 45.2 nGyair s−1. Additionally, this film demonstrates good X‐ray imaging performance with a spatial resolution of 14.76 line pairs (lp) mm−1 and shows exceptional stability under prolonged X‐ray exposure.
Funder
National Research Foundation of Korea
Subject
Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials