TY - JOUR

T1 - B(I)-Site Alkali Metal Engineering of Lead-Free Perovskite Nanocrystals for Efficient X-Ray Detection and Imaging

AU - Wang, Zhongyi

AU - Chen, Junsheng

AU - Xu, Xin

AU - Bai, Tianxin

AU - Kong, Qingkun

AU - Yin, Hong

AU - Yang, Yang

AU - Yu, William W.

AU - Zhang, Ruiling

AU - Liu, Xiaojing

AU - Han, Keli

N1 - Funding Information: This work was financially supported by the Taishan Scholar Project of Shandong Province of China, the Scientific Research Starting Foundation of Outstanding Young Scholar of Shandong University, the National Natural Science Foundation of China (Grant No. 22103050) and the Open Fund of the State Key Laboratory of Molecular Reaction Dynamics in DICP, CAS, Program of Young Scholars Future Program of Shandong University, Novo Nordisk Foundation (NNF22OC0073582). Publisher Copyright: © 2024 Wiley-VCH GmbH.

PY - 2024

Y1 - 2024

N2 - Lead-free metal halide double perovskites have emerged as promising scintillators owing to their superior optoelectronic properties, low-cost and solution processability. However, it is still challenging to develop high-performance flexible X-ray scintillators based on the B(I)-site alkali metal modulation in lead-free double perovskite nanocrystals (NCs). Herein, a series of novel Cs2B(I)GdCl6 (B: Li, Na, K) of double perovskite A2B(I)M(III)X6 NCs structures are successfully synthesized, the optical and scintillator properties of which are significantly sensitive to the B(I)-site alkali metals with the doping of Sb3+. They showed efficient self-trapped exciton (STE) emission with high photoluminescence quantum yield (PLQY) and exhibited the highest X-ray detection limit (86 nGyair s−1) and excellent spatial resolutions (>15 lp mm−1). The femtosecond transient absorption measurement and theoretical analysis further revealed that the B(I)-site alkali metal fundamentally balanced the exciton–phonon coupling with appropriate STEs formation energy barrier and the electron localization and thus improved the optical and scintillator properties. This B(I)-site alkali metal engineering offers a strategy to develop bright luminescent double perovskite NCs for X-ray detection and imaging devices.

AB - Lead-free metal halide double perovskites have emerged as promising scintillators owing to their superior optoelectronic properties, low-cost and solution processability. However, it is still challenging to develop high-performance flexible X-ray scintillators based on the B(I)-site alkali metal modulation in lead-free double perovskite nanocrystals (NCs). Herein, a series of novel Cs2B(I)GdCl6 (B: Li, Na, K) of double perovskite A2B(I)M(III)X6 NCs structures are successfully synthesized, the optical and scintillator properties of which are significantly sensitive to the B(I)-site alkali metals with the doping of Sb3+. They showed efficient self-trapped exciton (STE) emission with high photoluminescence quantum yield (PLQY) and exhibited the highest X-ray detection limit (86 nGyair s−1) and excellent spatial resolutions (>15 lp mm−1). The femtosecond transient absorption measurement and theoretical analysis further revealed that the B(I)-site alkali metal fundamentally balanced the exciton–phonon coupling with appropriate STEs formation energy barrier and the electron localization and thus improved the optical and scintillator properties. This B(I)-site alkali metal engineering offers a strategy to develop bright luminescent double perovskite NCs for X-ray detection and imaging devices.

KW - alkali metal

KW - flexible scintillator

KW - lead-free perovskite

KW - nanocrystals

KW - X-ray detection

U2 - 10.1002/adom.202302617

DO - 10.1002/adom.202302617

M3 - Journal article

AN - SCOPUS:85182436474

JO - Advanced Optical Materials

JF - Advanced Optical Materials

SN - 2195-1071

ER -