Combustion synthesis and upconversion luminescence properties of Er3+, Yb3+ doped gadolinium oxide nanophosphor

Gd2O3: Er3+, Yb3+ Nanophosphor prepared by combustion synthesis method.  Optical and Upconversion luminescence properties of rare earth doped nanophosphors were studied. The nanophosphors were characterized using Scanning electron microscopy, X-ray diffraction and ultraviolet–visible absorption spectroscopy. The results of XRD show cubic phase can be obtained, the average crystalline size could be calculated as 38 and 49nm respectively, which coincided with the results from SEM images. The UV- Vis optical spectra were also studied. Upconversion luminescence spectra of samples under the range of 980 nm, excitation were investigated. The strong red and weak green emission was observed. The possible upconversion luminescence mechanisms for Er3+, Yb3+ doped gadolinium nanophosphor were also discussed

Studies on thermoluminescence parameters of erbium doped Y2O3 nanophosphors

The thermoluminescence (TL) glow curve of Y2O3:Er3+ with different radiation time has been studied. The experimental glow curve shows the presence of two peaks at linear heating rate 10°C/min. The activation Energy and frequency factor are determined by thermoluminescence glow curve

Thermoluminescence Study of Y2O3: Tb

Nanophosphors were prepared by the combustion technique using yttria and terbia powder as precursors and urea as fuels. The particle is investigated by X-ray diffraction analysis. X-ray diffraction patterns confirm the formation of pure cubic phase of Y2O3 .The resulting product was characterized by FTIR spectra to evaluate the vibrational feature of the sample. TL emission spectra show intense peak around 520 nm

Optical properties of calcium aluminate phosphors

Thermoluminescence properties of CaAl2O4 was studied. It was found that firstly the TL intensity increases with increase in UV irradiation time and it attains a maximum value for 20 minute irradiation time. TL intensity decreases with further increase in irradiation time

X-ray diffraction: a powerful method of characterizing nanomaterials

X-ray diffraction techniques are a very useful characterization tool to study, non-destructively, the crystallographic structure, chemical composition and physical properties of materials and thin films. It can also be used to measure various structural properties of these crystalline phases such as strain, grain size, phase composition, and defect structure. XRD is also used to determine the thickness of thin films, as well as the atomic arrangements in amorphous materials such as polymers. This paper reports the importance of X-ray diffraction technique for the characterization of nanomaterials

Thermoluminescence of ï§-irradiated SrAl2O4:Dy

Thermoluminescence (TL) properties of ï§-irradiated Strontium Aluminate doped with Dy (10% molar concentration) was studied. The phosphor was synthesized by combustion method using urea as a reducer at initiating temperature of 600oC.  Dy doped SrAl2O4 is a good dosimeter having linear response upto 2360 Gy of ï§-dose. The kinetic parameter have been calculated using Chen’s glow curve method

Thermoluminescence of Cu doped ZnS nanoparticles

ZnS nanoparticles doped with Cu were synthesized by wet chemical route method at 4°C temperature. We have investigated the Thermoluminescence (TL) properties of the undoped ZnS and Cu doped ZnS with increase in Cu concentration from 0.5 millimole to 1.5 millimole and also study for different weight of Sodium Hexa Meta Phosphate (SHMP) capping agent from 2gm to 10gm. The XRD studies indicate that most of the samples are cubic in nature. The broadening of peaks tends to increase with increasing weight of capping agent showing decrease in particle size. The crystalline size computed using Scherer formula is found 2nm to 3nm. Absorption spectra show blue shift with different weight of capping agent. TL glow curve shows a single peak at 543 K temperature. Variation in TL intensity as a function of copper concentration is studied and 1mM is found to be the optimum concentration for TL. The trap parameters namely, activation energy (E), order of kinetics (b) and frequency factor(s) of ZnS: Cu sample have been determined using Chen’s method. The effect of heating rates and UV radiation dose for different time on TL glow curve has also been studied

Effect of firing temperature on the particles size of Gd2O3: Eu doped nanophosphors

The paper reports that synthesis and characterization of Eu2+ doped Gd2O3 nanophosphors prepared by combustion synthesis. It has been reported that the effect of synthesis temperature on particle size dependence phenomenon of rare earth doped nanophosphors. The sample was characterized by XRD pattern and FTIR study. Synthesized sample shows cubic structure verified by the XRD results.  Size of the particle was caculated by scherer equation the avarage size obtained 15, 23 and 55 at 4000C, 5000C and 6000C respectively. In this synthesis urea used as a fuel for created reducing atmosphere during sample preparation.&nbsp

Thermoluminescence and Mechanoluminescence studies of (Cd0.95 Zn0.05)S: Ag doped phosphor

Through the execution of experimental investigation, mechanoluminescence of (Cd,Zn)S: Ag phosphor was studied which is synthesized by solid state reaction. In the observation, the peak value of ML depends on different concentration. It is seen that ML intensity increases with Ag ion concentration in (Cd, Zn)S phosphor. The peak value of TL depends on the different UV-irradiation time. It is seen that as UV-irradiation exposure increases the TL intensity also increases