Thermoluminescence and photoluminescence studies on γ‐ray‐irradiated Ce³⁺,Tb³⁺‐doped potassium chloride single crystals

Abstract

Single crystals of KCl doped with Ce(3+),Tb(3+) were grown using the Bridgeman-Stockbarger technique. Thermoluminescence (TL), optical absorption, photoluminescence (PL), photo-stimulated luminescence (PSL), and thermal-stimulated luminescence (TSL) properties were studied after γ-ray irradiation at room temperature. The glow curve of the γ-ray-irradiated crystal exhibits three peaks at 420, 470 and 525 K. F-Light bleaching (560 nm) leads to a drastic change in the TL glow curve. The optical absorption measurements indicate that F- and V-centres are formed in the crystal during γ-ray irradiation. It was attempted to incorporate a broad band of cerium activator into the narrow band of terbium in the KCl host without a reduction in the emission intensity. Cerium co-doped KCl:Tb crystals showed broad band emission due to the d-f transition of cerium and a reduction in the intensity of the emission peak due to (5)D3 -(7)F(j) (j = 3, 4) transition of terbium, when excited at 330 nm. These results support that energy transfer occurs from cerium to terbium in the KCl host. Co-doping Ce(3+) ions greatly intensified the excitation peak at 339 nm for the emission at 400 nm of Tb(3+). The emission due to Tb(3+) ions was confirmed by PSL and TSL spectra.

Large-Sized Nitrogen-Containing Biphenyl-Doped p-Terphenyl Crystals with Tunable Luminescence for Organic Scintillators

“…Fortunately, because organic crystals have the advantages of low cost, easy preparation, a wide variety of materials, and resistance to deliquescence, they have shown application potential in the field of X-ray detection and imaging, arousing the interest of researchers. − However, the scintillator performance of organic crystals still needs to be continuously improved . The doping strategy is considered an effective method to enhance the scintillation performance of crystals. − In recent years, unique tunable luminescence properties of organic materials can be achieved via a controllable doping strategy, which can be applied to X-ray detection. When the X-ray scintillator is used in conjunction with photomultiplier tubes in radiation detectors, specific types of photomultiplier tubes can only match particular colors of X-ray-induced luminescence, so the tunable luminescence properties of the scintillator play an important role in the X-ray detection system. ,− This inspired us to study the fluorescence regulation of p -terphenyl organic scintillators in different bands by nitrogen-containing biphenyl doping under X-ray irradiation.…”