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Ca 2 Al 2 SiO 7 phosphors having various concentration of Ce 3? were synthesized by combustion-assisted method at initiating temperature of 600°C, using urea as a fuel and its XRD, SEM, TEM and EDX were studied. X-ray diffraction (XRD) pattern indicates that the crystal structure of Ca 2 Al 2 SiO 7 is mainly tetragonal and particle size of prepared phosphor was determined by TEM. Scanning electron microscope (SEM) image was recorded to observe the surface morphology. Mechanoluminescence (ML) and thermoluminescence (TL) properties of Ca 2 Al 2 SiO 7 :Ce 3? phosphors was also investigated. The TL intensity of Ca 2 Al 2 SiO 7 :Ce 3? was recorded for different exposure time of c-irradiation and it was observed that TL intensity is maximum for c dose of 1180 Gy. The increase in TL intensity indicates that the concentration of traps increases with c exposure time. The peak of ML intensity versus time curve increases linearly with increasing impact velocity of the moving piston. The ML intensity increases by increasing c irradiation time up to 1180 Gy. The ML and TL spectra of Ca 2 Al 2 SiO 7 :Ce 3? phosphor exhibits a sharp emission at 400 nm wavelength due to transition of Ce 3? ions. Mechanism of TL and ML excitation and suitability of Ca 2 Al 2 SiO 7 :Ce 3? phosphor for radiation dosimetry have been discussed.

Ce(3+)-doped calcium aluminosilicate phosphor was prepared by a combustion-assisted method at an initiating temperature of 600°C. Structural characterization was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The absorption spectra of Ca2Al2SiO7:Ce(3+) showed an absorption edge at 230 nm. The optical characterization of Ca2Al2SiO7:Ce(3+) phosphor was investigated in a fracto-mechanoluminescence (FML) and thermoluminescence (TL) study. The peak of ML intensity increased as the height of impact of the moving piston increased. The TL intensity of Ca2Al2SiO7:Ce(3+) was recorded for different exposure times of UV and γ-irradiation and it was observed that TL intensity was maximum for a UV irradiation time of 30 min and for a γ-dose of 1180 Gy. The TL intensity had three peaks for UV irradiation at temperatures 82°C, 125°C and 203°C. Also the TL intensity had a single peak at 152°C for γ-irradiation. The TL and ML emission spectra of Ca2Al2SiO7:Ce(3+) phosphor showed maximum emission at 400 nm. The possible mechanisms involved in the TL and ML processes of the Ca2Al2SiO7:Ce(3+) phosphor are also explained.

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A series of Ce ion single-doped Ca Al SiO phosphors was synthesized by a combustion-assisted method at an initiating temperature of 600 °C. The samples were annealed at 1100 °C for 3 h and their X-ray diffraction patterns confirmed a tetragonal structure. The phase structure, particle size, surface morphology and elemental analysis were analyzed using X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy techniques. Thermoluminescence (TL) intensity increased with increase in ultraviolet (UV) light exposure time up to 15 min. With further increase in the UV irradiation time the TL intensity decreases. The increase in TL intensity indicates that trap concentration increased with UV exposure time. A broad peak at 121 °C suggested the existence of a trapping level. The peak of mechanoluminescence (ML) intensity versus time curve increased linearly with increasing impact velocity of the moving piston. Mechanoluminescence intensity increased with increase in UV irradiation time up to 15 min. Under UV-irradiation excitation, the TL and ML emission spectra of Ca Al SiO :Ce phosphor showed the characteristic emission of Ce peaking at 400 nm (UV-violet) and originating from the Ce transitions of 5d-4f ( F and F ). The photoluminescence (PL) emission spectra for Ca Al SiO :Ce were similar to the ML/TL emission spectra. The mechanism of ML excitation and the suitability of the Ca Al SiO :Ce phosphor for radiation dosimetry are discussed. Copyright © 2016 John Wiley & Sons, Ltd.