Entity

Time filter

Source Type


Singh V.S.,Shri Ramdeobaba Kn Engineering College | Joshi C.P.,Shri Ramdeobaba Kn Engineering College | Moharil S.V.,Rashtrasant Tukadoji Maharaj Nagpur University
Journal of Alloys and Compounds | Year: 2013

LiBaF3 has great potential applications as X-ray storage phosphor, slow neutron imaging, scintillator, vacuum ultraviolet (VUV) optical lithography, etc. Conventionally, LiBaF3 is prepared by solid state reaction between the constituent fluorides. However, the preparation of phase pure material and especially single crystals is rather tricky due to incongruent melting. For the first time, a wet chemical preparation of rare earth activated LiBaF3 is described here. As precipitated powders containing Ce 3+ or Tb3+ exhibited characteristic luminescence. For observing Eu2+ emission, it was necessary to heat the powders in a reductive atmosphere. It is suggested that phosphors prepared by this method may prove useful in applications like OSL, X-ray imaging, etc. which do not require large single crystals. © 2013 Elsevier B.V. All rights reserved. Source


Ingole D.K.,Shri Ramdeobaba Kn Engineering College | Joshi C.P.,Shri Ramdeobaba Kn Engineering College | Moharil S.V.,Rashtrasant Tukadoji Maharaj Nagpur University | Muthal P.L.,Indian National Environmental Engineering Research Institute | Dhopte S.M.,Indian National Environmental Engineering Research Institute
Journal of Luminescence | Year: 2011

Intense photoluminescence is reported for hydrated bromides of Gd, La and Y (LaBr 3·7H 2O, CeBr 3·7H 2O, YBr 3·8H 2O and GdBr 3·n H 2O) prepared by the wet chemical method and activated with Ce 3. Intensities are comparable to that for a commercial phosphor (SrB 4O 7:Eu 2 - Sylvania 2052). Luminescence in hydrated salt is usually quenched. The observation of intense luminescence in hydrated bromides is remarkable. © 2011 Elsevier B.V. All rights reserved. Source


Joshi C.P.,Shri Ramdeobaba Kn Engineering College | Moharil S.V.,Rashtrasant Tukadoji Maharaj Nagpur University
International Journal of Self-Propagating High-Temperature Synthesis | Year: 2012

At least four compounds, viz. LiAlO 2, LiAl 5O 8, Li 5AlO 4 and Li 2Al 4O 7, are known in the Li 2O-Al 2O 3 system. These compounds are important for several technological applications. Combustion synthesis of these compounds using urea as a fuel was attempted. LiAlO 2 and LiAl 5O 8 could be successfully prepared by choosing the starting materials in required stoichiometric ratios. Li 2Al 4O 7 was not obtained as a pure phase; γ-LiAlO 2 was formed as an impurity phase. Li 5AlO 4 could not be prepared by combustion process. Some phosphors based on these aluminates could also be prepared. Activation of these aluminates with Fe 3+, Mn 4+, Cu +, etc. was successfully achieved. Excitation and emission spectra for LiAl 5O 8: Fe 3+, LiAl 5O 8: Mn 2+, and Li 2Al 4O 7: Cu + are reported. © 2012 Allerton Press, Inc. Source


Gupta K.V.K.,Kwality Photonics Pvt. Ltd. | Yadav P.,Shri Ramdeobaba Kn Engineering College | Joshi C.P.,Shri Ramdeobaba Kn Engineering College | Moharil S.V.,Rashtrasant Tukadoji Maharaj Nagpur University
Applied Physics B: Lasers and Optics | Year: 2011

YAG:Ce is an important phosphor having applications in various fields ranging from solid state lighting to scintillation detectors. YAG phosphors doped with activators are mainly synthesized by solid state reaction techniques that require high sintering temperatures (above 1500° C) to eliminate YAM and YAP phases. Though several soft chemical routes have been explored for synthesis of YAG, most of these methods are complex and phase pure materials are not obtained in one step, but prolonged annealing at temperatures around 1000° C or above become necessary. One step combustion synthesis of YAG:Ce3+ and related phosphors carried out at 500° C furnace temperature is reported here. Activation with Ce 3+ could be achieved during the synthesis without taking recourse to any post-combustion thermal treatment. LEDs prepared from the combustion synthesized YAG:Ce 3+, exhibited properties comparable to those produced from the commercial phosphor. © 2011 Springer-Verlag. Source


Pote S.S.,Shri Ramdeobaba Kn Engineering College | Joshi C.P.,Shri Ramdeobaba Kn Engineering College | Moharil S.V.,Rashtrasant Tukadoji Maharaj Nagpur University | Muthal P.L.,Indian National Environmental Engineering Research Institute | Dhopte S.M.,Indian National Environmental Engineering Research Institute
Physica B: Condensed Matter | Year: 2011

Some compounds with fluorite structures in the system CaF 2YF 3 were prepared by precipitation followed by thermal annealing at 1000 °C. Photoluminescence spectra of Ce 3 and Eu 2 were studied. In this host, Ce 3 exhibits PL, which is totally different from that observed for the constituent fluorides. Eu 2 emission, on the other hand, is almost the same as that for CaF 2. The changes are explained in terms of the defect structure of Ca 1-xY xF 2x. © 2011 Elsevier B.V. All rights reserved. Source

Discover hidden collaborations