Defects in scintillators based on ZnS–ZnSe solid solutions

Continuous Band-Gap Reduction on ZnO Submicrorods via Covering with ZnS1−xSex or ZnSe1−xTex Alloy in Core/Sheath Morphology

“…The lattice parameters of w-ZnS 1− x Se x ( x = 0, 0.25, 0.5, 0.75, 0.9) and s-ZnSe 1− x Te x ( x = 0, 0.8, 0.9, 1) alloys are plotted against the composition in Figure . The lattice parameters of the sheath alloys show a linear dependence on the composition following Vegard’s law, which is in good agreement with the previous reports. , Therefore, the formation of the homogeneous alloy sheath with the expected compositions on the ZnO core is concluded. Although at x = 1, the end-point ZnO/w-ZnSe cable could not be made under our experimental conditions, the extrapolation of the fitted line generates a = 4.008 Å and b = 6.557 Å for w-ZnSe (open circle and square in Figure a), being consistent with the JCPDS 15-0105 data ( a = 3.996 Å and b = 6.550 Å).…”

“…The bowing parameters are 0.87 eV for w-ZnS 1− x Se x and 1.41 eV for s-ZnSe 1− x Te x alloy sheaths. The latter falls in the reported range of 1−1.62 eV for the bulk s-ZnSe 1− x Te x alloy, and the former is larger than the reported range of 0−0.65 eV . This deviation may be attributed to the extreme sensitivity of the band structure to bond deformations, which may be related to the large lattice mismatch between the w-ZnS 1− x Se x alloy and w-ZnO (16−23%).…”

Scintillation and luminescence in transparent colorless single and polycrystalline bulk ceramic ZnS

“…It is thus extremely likely that copper and oxygen impurities are critical for producing optically active defects in undoped CVD ZnS. Thermoluminescence and x-ray (45-keV) excitation measurements of doped Zn(S,Se) solid solutions showed that copper-doped, and not silver-doped, materials exhibited bright outputs [40]. Self-activated blue luminescence spectra from Zn(S,O S ) solid solutions is very similar to those of silver and copper-blue ZnS luminescence, suggesting that the activator ions are physically located in regions of high oxygen concentration.…”