(C6H5C2H4NH3)2PbBr4 single crystals substituted with various concentrations of In (5, 10, 25, and 50%) were grown by the solvent diffusion method, and the effect of In-substitution on ...photoluminescence (PL) and scintillation properties were investigated. PL and scintillation peaks due to excitons confined in inorganic layers were observed, and the decay times were consistent with those of the free excitonic luminescence. The photoluminescence quantum yields of the 5, 10, 25, and 50% In-substituted crystals were respectively 23.0, 24.7, 26.0, and 25.2%. The light yield of the 25% In-substituted crystal was estimated to be 14100 photons/MeV from the pulse height spectrum under 137Cs γ-rays irradiation.
•In:(C6H5C2H4NH3)2PbBr4 crystals were grown by the solvent diffusion method.•Free excitonic luminescence was observed.•Light yield of the 25% In-substituted crystal was 14,100 photons/MeV.
We synthesized the Nd-doped Bi
4
Ge
3
O
12
(BGO) single crystals with different concentrations of Nd (0.1, 0.5, and 1%) by the floating zone method and evaluated the photoluminescence (PL) and ...scintillation properties. In both the PL and scintillation spectra, intrinsic luminescence of BGO was observed at 400–600 nm. In addition, emission peaks due to the 4f–4f transitions of Nd
3+
were observed in the near-infrared range. The 0.5% Nd-doped sample indicated the highest quantum yield of 42.9% among the samples. All the samples showed good linearity between X-ray exposure dose rate and the emission intensity in the NIR range. The lowest detectable dose rates were 0.06 Gy/h in the 0.1 and 1% Nd-doped BGO samples, and that of the 0.5% Nd-doped BGO sample was 0.01 Gy/h.
Undoped, 0.5, 1.0, and 2.0% Nd-doped Bi4Si3O12 (BSO) crystals were synthesized by the floating zone method. Regarding photoluminescence (PL) properties, all samples had emission peaks due to the ...6p–6s transitions of Bi3+ ions. In addition, the Nd-doped samples had emission peaks due to the 4f–4f transitions of Nd3+ ions as well. The PL quantum yield of the 0.5, 1.0, and 2.0% Nd-doped samples in the near-infrared range were 67.9, 73.0, and 56.6%, respectively. Regarding X-ray-induced scintillation properties, all samples showed emission properties similar to PL. Afterglow levels at 20 ms after X-ray irradiation of the undoped, 0.5, 1.0, and 2.0% Nd-doped samples were 192.3, 205.9, 228.2, and 315.4 ppm, respectively. Dose rate response functions had good linearity from 0.006 to 60 Gy/h for the 1.0% Nd-doped BSO sample and from 0.03 to 60 Gy/h for the other samples.
(C6H5C2H4NH3)2PbCl4 and (n-FC6H4C2H4NH3)2PbCl4 (n = 2, 3, and 4) crystals were grown by the slow-cooling method, and the optical and scintillation properties were investigated. From the X-ray ...diffraction pattern, F-substitution in a benzene ring makes the lattice constant larger than (C6H5C2H4NH3)2PbCl4. They exhibited photoluminescence and scintillation peaks due to the recombination of the self-trapped excitons confined in inorganic layers at 400–700 nm. The afterglow levels at 20 ms after X-ray irradiation for 2 ms were 100–600 ppm. From the pulse height spectra under 241Am α-ray (5.5 MeV) irradiation, the light yields of (C6H5C2H4NH3)2PbCl4, (3-FC6H4C2H4NH3)2PbCl4, and (4-FC6H4C2H4NH3)2PbCl4 samples were calculated to be 1,400, 1,800, and 1,700 ph/5.5 MeV-α.
•(FC6H4C2H4NH3)2PbCl4 crystals were grown by the slow cooling method.•All the crystals showed the luminescence due to the recombination of the self-trapped excitons confined in inorganic layers.•The (4-FC6H4C2H4NH3)2PbCl4 crystal showed the highest quantum yield (QY) in the present crystals.•The light yields of the (3-FC6H4C2H4NH3)2PbCl4 and (4-FC6H4C2H4NH3)2PbCl4 crystals surpassed that of the unsubstituted crystal.
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