Key points are not available for this paper at this time.
Chemical design of luminescent metal halides as high-performance X-ray scintillators is in urgent demand. Herein, rare earth Eu(II) was innovated as a B-site cation to create brand-new metal halide scintillators, and a regulating bandgap was further developed via organic molecule design based on the same anionic chain of EuBr3MeOHnn–, namely, CatEuBr3MeOH Cat = 1-butyl-1-methylpiperidinium (PP14), 1-propyl-1-methylpiperidinium (PP13), and 1-ethyl-3-methylimidazolium (Emim). Owing to the smaller bandgap of EmimBr, EmimEuBr3MeOH possesses an enhanced light yield of 43,000 ± 100 ph MeV–1 as scintillators. The conjugated attribute of Emim+ also contributes to π–π stacking, resulting in a more rigid structure, reducing the nonradiative transition. The scintillator film by using EmimEuBr3MeOH emanates spatial resolution above 10 lp mm–1. This study provides a design principle by B-site cations screening and bandgap engineering of organic cations for enhancing the light yield property and exemplifies novel materials in the family of Eu(II) halide hybrids as potential scintillators.
Jin et al. (Fri,) studied this question.