Transparent Microcomposite Films Based on a Ce-Doped Li₆Gd(BO₃)₃ Scintillator for Radiation Detection

Abstract

Scintillators are widely used for high-energy radiation detection. Hybrid inorganic–organic composite scintillators with high light yields, high light decay rates, excellent stability, and low costs are in great demand. Here, we report a novel scintillator composed of Ce-doped Li 6 Gd(BO 3 ) 3 (LGBO) microphosphors (MPs) and polymethyl methacrylate for X-ray and thermal neutron detection. The Ce-doped LGBO MPs, fabricated using a facile high-temperature solid-state reaction method, exhibit intense blue light at 416 nm under X-ray and UV excitation and have a high photoluminescence quantum yield of ∼63%. More importantly, the composite scintillator based on these MPs has excellent transparency and luminescence intensity. The luminescence integral intensity of composite scintillators is superior to that of commercial CsI:Na under X-ray excitation, and the light yield under thermal neutron irradiation is 21,000 photons/thermal neutron. The scintillation decay time is found to be below 600 ns. The neutron−gamma signal discrimination and neutron detection efficiency of the composite scintillators are acceptable for practical application. There is an excellent separation between neutron and background events. It represents significant improvements in scintillator performances, especially for reliable thermal neutron scintillators that are likely to improve the data qualities of scientific instruments, including charge-coupled device-based imagers and Anger logic-based position-sensitive detectors in neutron user facilities.

Bright lead-free Cs3Cu2I5 perovskite scintillators for thermal neutron detection

“…The measurement details can be found in our previous report. 18 Thermal neutron radiation was obtained from 252 Cf (average energy = 25 meV, emission rate = 2000 n s À1 ) with a polythylene (thickness = 500 mm) moderated cavity. Gamma radiation was obtained from 60 Co (average energy = 1.2 MeV) and 137 Cs (energy = 0.662 MeV).…”

“…16,17 Other Li, Gd, and B-containing compounds, such as Li 6 Gd(BO 3 ) 3 (LGBO), Ce:Gd 3 (Al,Ga) 5 O 12 (GAGG), CsLiCeCl 6 , and LiCaAlF 6 , cannot satisfy the stringent requirements of neutron detection one way or another. [18][19][20][21][22] Lead-halide perovskites are promising for advanced optoelectronic devices, such as solar cells, 23 photodetectors, 24 lightemitting diodes, 25 photo-catalysts, 26 and mersisters, 27 due to their excellent photoluminescence and optoelectronic performances. However, the toxicity of lead and low stability limit their applications.…”

“…16,17 Other Li, Gd, and B-containing compounds, such as Li 6 Gd(BO 3 ) 3 (LGBO), Ce:Gd 3 (Al,Ga) 5 O 12 (GAGG), CsLiCeCl 6 , and LiCaAlF 6 , cannot satisfy the stringent requirements of neutron detection one way or another. 18–22…”