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The present paper reports the synthesis and characterization of Sr3MgSi2O8 phosphor. The phosphor was prepared by solid state reaction method. Average crystal size for the phosphors yielded was in nanometre range, which was calculated by using X-ray diffraction analysis and confirmed by field emission gun scanning electron microscopy and transmission electron microscopy technique. Sample shows cubic structure and the particle size calculated by Scherer’s formula was around 48 nm. For recording TL glow curve every time 2 mg phosphor was irradiated by 254 nm UV source. Sample shows well resolved peak at 123 °C. Various parameters like heating rate and exposure time were optimized. The obtained glow curve for optimized condition of heating rate and UV exposure time was analysed by computerized glow curve deconvolution technique technique. Kinetic parameters were calculated by using Chen’s peak shape method for all the deconvoluted peaks.

ZrO2 samples with variable Gd3+ doping have been prepared by combustion synthesis method followed by annealing at 900 °C. The samples have been characterized by X-ray absorption, Scanning electron microscopy, and electron dispersive X-ray spectroscopy. The optical behaviour was also determined by recording excitation and emission spectroscopy of the phosphor. The emission spectrum contains intense peak at UV region along with peaks at visible region. All the peaks were obtained due to transitions between the energy levels of the Gd3+ ion.

Gd2O3:Pr3+ phosphor was synthesized by combustion synthesis method using glycerine as a fuel. The structural properties as well as the optical properties were investigated. The structural characterization was done by using X-ray diffraction and electron mircroscopic techniques. Optical property such as photoluminescence was investigated under 275 nm excitation. Emission spectra has intense peak in red region around 638 nm. CIE coordinates also confirms that the prepared phosphor behaves as a red emitting phosphor.

Er3+ doped Gd2O3 phosphors were prepared by using solution combustion synthesis method. The structural characterization and the luminescence behaviour of the prepared phosphors were determined and compared. Average crystal size for the phosphors yielded was in nanometre range from 6 to 48 nm, which was calculated by using XRD and confirmed by TEM technique. The compositional analysis was done by FTIR. Qualitative information regarding the elemental composition of powder sample was measured using EDX spectroscopy. EDX and FT-IR spectra confirm presence of Er3+ in the Gd2O3:Er3+ phosphors. For thermoluminescence (TL) studies the TL glow curves were recorded under two different excitations i.e. UV and gamma exposures. All the factors like dopant concentration, heating rate, exposure dose etc. were optimized for both the excitations. Various Kinetic parameters were calculated for TL glow curve recorded for all the optimized conditions. Computerized glow curve deconvolution analysis was carried out for optimized TL glow curve. Different kinetic parameters were also calculated for all the deconvoluted peaks.

Sr2MgSi2O7:Eu3+ and Sr2MgSi2O7:Eu3+, R+ (R+ = Li+, Na+ and K+) phosphors were prepared by conventional solid state reaction method. The crystal structures of synthesized phosphors were an akermanite type structure which belongs to the tetragonal crystallography. The thermoluminescence kinetic parameters such as activation energy, order of kinetics and frequency factor was calculated by peak shape method. In this work, the orange-red emission originated from the 5D0–7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+ ions could clearly be observed after samples were excited at 395 nm. Decay graph indicate that these phosphors also contain the fast and slow decay process. Mechanoluminescence intensity of prepared Sr2MgSi2O7:Eu3+ and Sr2MgSi2O7:Eu3+, R+ (R+ = Li+, Na+ and K+) phosphors were increases linearly with the increasing impact velocity of moving piston (load). CIE color chromaticity diagram confirm that the prepared phosphors would emit orange-red color. Thus the present investigation indicating that this phosphor may be a potential candidate for stress sensors. The dopant R+ (R+ = Li+, Na+ and K+) as charge compensator in Sr2MgSi2O7:Eu3+ can further enhance luminescence intensity, and the emission intensity of Sr2MgSi2O7:Eu3+ doping Li+ is higher than that of Na+ or K+.

The SrAl2O4:Eu2+ and SrAl2O4:Eu3+ phosphors were prepared by the traditional high temperature solid state reaction method. The crystal structures of the prepared phosphors were consistent with standard monoclinic phase with a space group P21. The different TL kinetics parameters [activation energy (E), frequency factor (s) and order of the kinetics (b)] were evaluated and compared by using the peak shape method. Under the ultra-violet excitation (344 nm), the SrAl2O4:Eu2+ phosphor would emit green light, belonging to the broad emission band ascribed to the 4f65d1 → 4f7 transition. The emission spectrum of SrAl2O4:Eu3+ phosphor was consisted of two emission peaks at 590 and 615 nm, which were attributed to 5D0 → 7F1 and 5D0 → 7F2 of Eu3+ ions. The strongest excitation band at 396 nm can be assigned to 7F0 → 5L6 transition of Eu3+ ions due to the typical f–f transitions of 4f6 configuration. Commission International de I’Eclairage color coordinates of prepared SrAl2O4:Eu2+ and SrAl2O4:Eu3+ phosphors were suitable as green and orange-red light respectively. The mechanoluminescence (ML) intensity of prepared SrAl2O4:Eu2+ and SrAl2O4:Eu3+ phosphors increase linearly with increasing impact velocity of the moving piston (load). Thus the present investigation indicates that the piezoelectricity was responsible to produce ML in sintered phosphors. Decay rates for different impact velocities were also calculated using curve-fitting techniques. The time of the peak ML and the rate of decay did not change significantly with respect to increasing impact velocity of the moving piston and peak ML intensity varied linearly.

A new orange–red europium doped strontium calcium magnesium di-silicate (SrCaMgSi2O7:Eu3+) phosphor was prepared by the traditional high temperature solid state reaction method. The tetragonal structure of the orange–red compound was confirmed by the X-ray diffraction (XRD) technique. An energy dispersive X-ray spectroscopy (EDS) confirms the presence of elements in sintered phosphor. The thermoluminescence (TL) kinetic parameters such as activation energy, order of kinetics and frequency factor was calculated by peak shape method. In this work, the orange–red emission originated from the 5D0–7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+ ions could clearly be observed after sample was excited at 396 nm. Commission International de I’Eclairage color chromaticity diagram, TL spectra and ML spectra confirms the prepare SrCaMgSi2O7:Eu3+ phosphor exhibits orange–red emission. The mechanoluminescence (ML) intensity of SrCaMgSi2O7:Eu3+ phosphor increases linearly with increasing impact velocity of the moving piston which suggests that this phosphor can be used as sensors to detect the stress of an object. Thus, the present investigation indicates the piezo-electricity was responsible to produce ML in prepared SrCaMgSi2O7:Eu3+ phosphor.

A series of rare earth doped and co-doped di-strontium magnesium di-silicate phosphors namely: Sr2MgSi2O7:Ce3+, Sr2MgSi2O7:Eu2+ and Sr2MgSi2O7:Eu2+, Ce3+ were prepared by the solid state reaction method. The crystal structures of sintered phosphors were an akermanite type structure which belongs to the tetragonal crystallography. The chemical compositions of sintered phosphors were confirmed by energy dispersive X-ray spectroscopy (EDS). Under the ultraviolet excitation, the emission spectra of both Sr2MgSi2O7:Eu2+ and Sr2MgSi2O7:Eu2+, Ce3+ phosphors were composed of a broad band peaking at 460 nm, belonging to the broad emission band. When the Sr2MgSi2O7:Eu2+ phosphor is co-doped with Ce3+ ions, thermouminescence, photoluminescence, afterglow and mechanoluminescence (ML) intensity were strongly enhanced. The Sr2MgSi2O7:Eu2+ phosphor showed some afterglow with short persistence time. By incorporation of Ce3+ ions, an efficient energy transfer from Ce3+ to Eu2+ was found and emission intensity of Sr2MgSi2O7:Eu2+ was enhanced. The ML intensities of Sr2MgSi2O7:Ce3+, Sr2MgSi2O7:Eu2+ and Sr2MgSi2O7:Eu2+, Ce3+ phosphors were proportionally increased with the increase of impact velocity, which suggests that these phosphors can be used as sensors to detect the stress of an object. Thus the present investigation indicates that the piezoelectricity is responsible to produce ML in prepared phosphors.

The Sr2Al2SiO7:Eu2+ and Sr2Al2SiO7:Eu3+ phosphors were prepared by the traditional high temperature solid state reaction method. The crystal structures of sintered phosphors were gehlenite type structure which belongs to the tetragonal crystallography with space group $$ {\rm P}\bar{42}_{1}{\rm m} $$ . Thermoluminescence properties of these phosphors were investigated and results were also compared. Under the ultra-violet excitation (345 nm), the Sr2Al2SiO7:Eu2+ phosphor would emit bluish-green (cyan) light, belonging to the broad emission band ascribed to the 4f 65d 1 → 4f 7 transition. The emission spectrum (λex = 395 nm) of Sr2Al2SiO7:Eu3+ phosphor were consisted of two emission peaks at 593 and 613 nm, which were attributed to 5D0 → 7F1 and 5D0 → 7F2 of Eu3+ ions. The strongest excited band at 395 nm can be assigned to 7F0 → 5L6 transition of Eu3+ ions due to the typical f–f transitions within Eu3+ of 4f 6 configuration. Commission International de I’Eclairage color coordinates of Sr2Al2SiO7:Eu2+ and Sr2Al2SiO7:Eu3+ phosphors were suitable as bluish-green and orange-red light emitting phosphors respectively. The mechanoluminescence (ML) intensity of Sr2Al2SiO7:Eu2+ and Sr2Al2SiO7:Eu3+ phosphors increase linearly with increasing impact velocity of the moving piston. Thus the present investigation indicates that the piezo-electrically induced de-trapping model is responsible to produce ML in sintered phosphors.

In this paper, we report the dysprosium doped di-calcium magnesium di-silicate namely Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were prepared by traditional high temperature solid state reaction method. Phosphors with optimum photo-luminescence intensity [Ca2MgSi2O7:Dy3+ (2 %)] were characterized by X-ray diffraction (XRD) technique. The crystal structure of sintered phosphors were an akermanite type which belongs to the tetragonal crystallography with space group $$ {\text{P}}\overline{ 4 2}_{1} {\text{m}} $$ . The chemical composition of the sintered phosphor Ca2MgSi2O7:Dy3+ (2 %) was confirmed by the energy dispersive X-ray spectroscopy (EDS). Under the ultraviolet excitation, the emission spectra of Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were composed of broad band with the characteristic emission of Dy3+ ions are peaking at 475 nm (blue), 577 nm (yellow) and 678 nm (red), originating from the transitions of 4F9/2 → 6Hj state (where j = 15/2, 13/2, 11/2). The combination of these three emissions constituted white light as indicated on the Commission Internationale de l’Eclairage chromaticity diagram. The possible mechanism of the prepared white light emitting Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were also investigated. Investigation on decay property show that phosphor held fast and slow decay process. The peak of mechanoluminescence (ML) intensity increases linearly with increasing impact velocity of the moving piston, which suggests that this phosphor can be used as sensors to detect the stress of an object. Thus the present investigation indicates that piezo-electricity is responsible to produce ML in prepared phosphors.

In the present investigation dysprosium doped strontium aluminate phosphor was prepared by combustion synthesis method. The crystal structure of the prepared phosphor was consistent with standard monoclinic phase with a space group P21. According to the TEM analysis, the particle size was found to be in the nanometer range. The trap parameters which are mainly activation energy (E), frequency factor (s) and order of the kinetics (b) were evaluated by using the peak shape method. Under the ultraviolet (365 nm) excitation, photoluminescence (PL) spectra showed characteristic emission bands at 480 (blue), 573 (yellow) and 670 nm (red) due to 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 transitions of Dy3+ ions. Combination of these three emissions constituted as white light confirmed by the Commission Internationale de L’Eclairage (CIE) chromatic coordinate diagram and possible mechanism of white light emitting SrAl2O4:Dy3+ phosphor was also investigated. The value of correlated color temperature (CCT) was found, well within the defined acceptable range (5965 K). The mechanoluminescence (ML) intensity of SrAl2O4:Dy3+ phosphor increases linearly with increasing impact velocity of the moving piston. Thus, the present investigation indicates the piezo-electricity was responsible to produce ML in prepared phosphor.