Metal halides have drawn great interest as luminescent
materials
and scintillators due to their outstanding optical properties. Exploring
new types of phosphors with easy production processes, excellent photophysical
properties, high light yields, and environmentally friendly compositions
is crucial and quite challenging. Herein, a novel Mn(II)-based metal
halide (4-BTP)2MnBr4 was produced using a facile
solvent evaporation method, which exhibited a strong green emission
peaking at 524 nm from the d–d transition of tetrahedral-coordinated
Mn2+ ion and a near-unity quantum yield. The prepared white
light-emitting diode device has a wide color gamut of 100.7% NTSC
with CIE chromaticity coordinates of (0.32, 0.32). In addition, (4-BTP)2MnBr4 demonstrates excellent characteristics in
X-ray scintillation, including a high light yield of 98 000
photons/MeV, a sensitive detection limit of 37.4 nGy/s, excellent
resistance to radiation damage, and successful demonstration of X-ray
imaging with high resolution at 21.3 lp/mm, revealing the potential
for application in diagnostic X-ray medical imaging and industry radiation
detection.