posted on 2024-01-23, 22:15authored byJie Zhang, Xin Wang, Wen-Qi Wang, Xiangyuan Deng, Cheng-Yang Yue, Xiao-Wu Lei, Zhongliang Gong
The increasing demands in optoelectronic applications
have driven
the advancement of organic–inorganic hybrid metal halides (OIMHs),
owing to their exceptional optical and scintillation properties. Among
them, zero-dimensional (0D) low-toxic manganese-based scintillators
have garnered significant interest due to their exceptional optical
transparency and elevated photoluminescence quantum yields (PLQYs),
making them promising for colorful light-emitting diodes and X-ray
imaging applications. In this study, two OIMH single crystals of (Br-PrTPP)2MnBr4 (Br-PrTPP = (3-bromopropyl) triphenylphosphonium)
and (Br-BuTPP)2MnBr4 (Br-BuTPP = (4-bromobutyl)
triphenylphosphonium) were prepared via a facile saturated crystallization
method. Benefiting from the tetrahedrally coordinated [MnBr4]2– polyhedron, both of them exhibited strong green
emissions peaked at 517 nm owing to the d–d electron transition
of Mn2+ with near-unity PLQYs of 99.33 and 86.85%, respectively.
Moreover, benefiting from the high optical transparencies and remarkable
luminescence properties, these manganese halides also exhibit excellent
radioluminescent performance with the highest light yield of up to
68,000 photons MeV–1, negligible afterglow (0.4
ms), and linear response to X-ray dose rate with the lowest detection
limit of 45 nGyair s–1. In X-ray imaging,
the flexible film made by the composite of (Br-PrTPP)2MnBr4 and PDMS shows an ultrahigh spatial resolution of 12.78 lp
mm–1, which provides a potential visualization tool
for X-ray radiography.