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Papers by Dhananjay Gahane
International Journal of Applied Ceramic Technology, 2010
A new combustion method for preparation of Dy 3+-doped La 2 Sn 2 O 7 nanocrystals is presented. T... more A new combustion method for preparation of Dy 3+-doped La 2 Sn 2 O 7 nanocrystals is presented. The morphologies of the as-synthesized nanocrystals are characterized by X-ray diffraction (XRD) and transmission electron micrograph (TEM). The pyrochlore structure nanocrystals less than 50 nm with a hexagonal morphology are synthesized for the first time. The luminescent properties of these nanocrystals have been investigated by fluorescence measurements at room temperature. The results indicate that the energy transfers from the La 2 Sn 2 O 7 host to dysprosium ions.
International Journal of Scientific Research in Science and Technology (IJSRST), 2018
In the present work, Sr 4-x Al 6 MoO 16 :xEu 3+ (x= 2,3,4 &5 %) red-emitting phosphors have been ... more In the present work, Sr 4-x Al 6 MoO 16 :xEu 3+ (x= 2,3,4 &5 %) red-emitting phosphors have been successfully synthesized by the combustion method and their photoluminescence characterization was performed. Photoluminescence spectra showed that the emission peaks at 593 (5 D 0 → 7 F 1) and 615 nm (5 D 0 → 7 F 2) for Eu 3+ are observed after excitation at 270 nm (i.e. Mo–O charge transfer band). Intense red emission of Eu 3+ in Sr 4-x Al 6 MoO 16 host lattice show the occupation of a non-centrosymmetric site by the rare earth ions in the host lattice. The emission intensity of Eu 3+ ions in the Sr 4-x Al 6 MoO 16 host largely enhanced with the concentration increasing of activator (Eu 3+). Intense characteristic emissions show no concentration quenching up to 3 mol% concentration of rare earth ion and the emission intensity reached the maximum at x=4%. Among these phosphors, Sr 4-x Al 6 MoO 16 :xEu 3+ synthesized at 750℃ exhibits the strongest red emission and appropriate CIE chromaticity coordinates (x=0.637, y=0.359) close to the NTSC standard value. It is shown that Sr 4-x Al 6 MoO 16 :xEu 3+ phosphors are demonstrating their potential suitability for application in solid state lighting.
We have synthesised red-emitting K 2 Sr (1-x) (MoO 4) 2 :xEu 3+ (x=0.05) phosphor by combustion s... more We have synthesised red-emitting K 2 Sr (1-x) (MoO 4) 2 :xEu 3+ (x=0.05) phosphor by combustion synthesis method and their photoluminescence characteristics were investigated. When the K2Sr(MoO4)2 system is doped with Eu 3+ ions, energy transfer occurs from MoO4 2-groups to Eu 3+ ions. The results show that all samples can be efficiently excited by UV (393 nm) light. A narrow emission spectra obtained shows intense red emission peaking at 617 nm. The characteristic emission spectrum is due to the 5 D 0-7 F 2 transition of Eu 3+. The red-emitting K2Sr(MoO4)2:Eu 3+ phosphor may be potential candidate in the fabrication of white light emitting diodes (LEDs).
International Journal of Applied Ceramic Technology, 2010
A new combustion method for preparation of Dy 3+-doped La 2 Sn 2 O 7 nanocrystals is presented. T... more A new combustion method for preparation of Dy 3+-doped La 2 Sn 2 O 7 nanocrystals is presented. The morphologies of the as-synthesized nanocrystals are characterized by X-ray diffraction (XRD) and transmission electron micrograph (TEM). The pyrochlore structure nanocrystals less than 50 nm with a hexagonal morphology are synthesized for the first time. The luminescent properties of these nanocrystals have been investigated by fluorescence measurements at room temperature. The results indicate that the energy transfers from the La 2 Sn 2 O 7 host to dysprosium ions.
International Journal of Scientific Research in Science and Technology (IJSRST), 2018
In the present work, Sr 4-x Al 6 MoO 16 :xEu 3+ (x= 2,3,4 &5 %) red-emitting phosphors have been ... more In the present work, Sr 4-x Al 6 MoO 16 :xEu 3+ (x= 2,3,4 &5 %) red-emitting phosphors have been successfully synthesized by the combustion method and their photoluminescence characterization was performed. Photoluminescence spectra showed that the emission peaks at 593 (5 D 0 → 7 F 1) and 615 nm (5 D 0 → 7 F 2) for Eu 3+ are observed after excitation at 270 nm (i.e. Mo–O charge transfer band). Intense red emission of Eu 3+ in Sr 4-x Al 6 MoO 16 host lattice show the occupation of a non-centrosymmetric site by the rare earth ions in the host lattice. The emission intensity of Eu 3+ ions in the Sr 4-x Al 6 MoO 16 host largely enhanced with the concentration increasing of activator (Eu 3+). Intense characteristic emissions show no concentration quenching up to 3 mol% concentration of rare earth ion and the emission intensity reached the maximum at x=4%. Among these phosphors, Sr 4-x Al 6 MoO 16 :xEu 3+ synthesized at 750℃ exhibits the strongest red emission and appropriate CIE chromaticity coordinates (x=0.637, y=0.359) close to the NTSC standard value. It is shown that Sr 4-x Al 6 MoO 16 :xEu 3+ phosphors are demonstrating their potential suitability for application in solid state lighting.
We have synthesised red-emitting K 2 Sr (1-x) (MoO 4) 2 :xEu 3+ (x=0.05) phosphor by combustion s... more We have synthesised red-emitting K 2 Sr (1-x) (MoO 4) 2 :xEu 3+ (x=0.05) phosphor by combustion synthesis method and their photoluminescence characteristics were investigated. When the K2Sr(MoO4)2 system is doped with Eu 3+ ions, energy transfer occurs from MoO4 2-groups to Eu 3+ ions. The results show that all samples can be efficiently excited by UV (393 nm) light. A narrow emission spectra obtained shows intense red emission peaking at 617 nm. The characteristic emission spectrum is due to the 5 D 0-7 F 2 transition of Eu 3+. The red-emitting K2Sr(MoO4)2:Eu 3+ phosphor may be potential candidate in the fabrication of white light emitting diodes (LEDs).