K K . Jayanthi | NIT warangal (original) (raw)

Papers by K K . Jayanthi

Research paper thumbnail of Lumino-magnetic YAG:Ce nanophosphors: novel synthesis routes for efficient luminescence and magnetic properties

J. Mater. Chem. C, 2014

Multifunctional lumino-magnetic YAG:Ce nanophosphors for LEDs and spintronics devices.

Research paper thumbnail of Electronic and luminescent characteristics of Aluminum doped ZnO nanocrystals

Electronic Materials Letters, 2015

donor levels and intrinsic acceptor centre. Both AZO samples exhibit n-type conduction with resis... more donor levels and intrinsic acceptor centre. Both AZO samples exhibit n-type conduction with resistivity of AZO prepared in inert (argon) ambient condition showing lower resistivity compared to the one synthesized in air atmosphere.

Research paper thumbnail of Fabrication of Luminescent, Magnetic Hollow Core Nanospheres and Nanotubes of Cr-Doped ZnO by Inclusive Coprecipitation Method 1

The Journal of Physical Chemistry C, 2010

... Chawla, S.; Jayanthi, K.; Kotnala, RK Phys. Rev. B 2009, 79, 125204 [CrossRef]. 18. Chawla, S... more ... Chawla, S.; Jayanthi, K.; Kotnala, RK Phys. Rev. B 2009, 79, 125204 [CrossRef]. 18. Chawla, S.; Jayanthi, K.; Kotnala, RK J. Appl. Phys. 2009, 106, 113923 [CrossRef]. 19. Sato, K.; Yoshida, HK Jpn. J. Appl. ... Venkatesan, M.; Fitzgerald, CB; Lunney, JG; Coey, JMD Phys. Rev. Lett. ...

Research paper thumbnail of Enhancement of luminescence in ZnMgO thin-film nanophosphors and application for white light generation

physica status solidi (a), 2008

Research paper thumbnail of Structure and luminescence of (Zn,Mg)O:Zn2+ nanophosphor films

Materials Letters, 2008

This article was published in an Elsevier journal. The attached copy is furnished to the author f... more This article was published in an Elsevier journal. The attached copy is furnished to the author for non-commercial research and education use, including for instruction at the author's institution, sharing with colleagues and providing to institution administration. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright

Research paper thumbnail of Observation of Nd3+visible line emission in ZnO : Nd3+prepared by a controlled reaction in the solid state

Journal of Physics D: Applied Physics, 2013

ABSTRACT Visible emission from ZnO is usually broadband and realizing line emission from rare ear... more ABSTRACT Visible emission from ZnO is usually broadband and realizing line emission from rare earth f–f transitions in ZnO at room temperature has proven to be difficult. A controlled solid-state reaction process with different standing times to synthesize rare earth doped (Nd 3+) zinc oxide (ZnO) has shown that sharp and intense line emission in the orange region (595 nm) could be realized under blue excitation, where both excitation and emission transitions occur between Nd 3+ levels situated intragap in ZnO. In addition, host-to-Nd 3+ energy transfer is also observed under band-to-band excitation. Incidentally, undoped ZnO synthesized by an identical process exhibits a broad green emission. Detailed characterization of the ZnO :Nd 3+ powder by x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, x-ray photoelectron spectroscopy, photoluminescence spectroscopy and time-resolved decay indicates a hexagonal phase with the presence of Nd 3+ in the ZnO lattice, forming spherical particles (∼200 nm) having a sharp visible emission with decay time in the microsecond range (9.60 µs). (Some figures may appear in colour only in the online journal)

Research paper thumbnail of Growth, microstructure, UV and orange pink emission from ZnO nanocones

Journal of Crystal Growth, 2008

ZnO nanocones are synthesized as freestanding powder as well as thin film by precipitation in a h... more ZnO nanocones are synthesized as freestanding powder as well as thin film by precipitation in a highly alkaline aqueous solution. X-ray diffraction demonstrated well-formed wurtzite crystal structure. The microstructure and morphology of individual nanocone were studied by transmission electron microscopy. Photoluminescence studies show strong UV emission in both powder and thin film form. Powder samples also show weak orange pink emission under UV excitation. High UV to visible emission ratio implies purity of the crystallites. However, the ZnO crystallites are also excitable by purple/blue light to emit in orange/red region and act as down conversion phosphor in the visible range indicating role of some intragap states. Fluorescence lifetime spectroscopy indicates fast recombination in hundreds of picoseconds range and complex charge transfer process in the microsecond range suggesting role of excitons and intragap states in the photophysical process.

Research paper thumbnail of Synthesis and optical properties of ZnO/MgO nanocomposite

Journal of Alloys and Compounds, 2008

... One of the authors (K. Jayanthi) is highly grateful to the Council of Scientific and Industri... more ... One of the authors (K. Jayanthi) is highly grateful to the Council of Scientific and Industrial Research (CSIR), India, for her fellowship under CSIR Diamond Jubilee Research Intern Scheme (No. ... [4] S. Choopun, RD Vispute, W. Yang, RP Sharma and T. Venkatesan, Appl. Phys. ...

Research paper thumbnail of Synthesis and surface modification of ZnO:Cu nanoparticles by silica and PMMA

Current Applied Physics, 2010

ZnO nanoparticles doped with Cu were synthesized by solid state reaction using different precurso... more ZnO nanoparticles doped with Cu were synthesized by solid state reaction using different precursor routes and varying growth environment. Average crystallite size varied from 40 to 100 nm depending upon synthesis temperature, lower temperature favouring smaller particle size. Scanning ...

Research paper thumbnail of Synthesis of Mn doped ZnO nanoparticles with biocompatible capping

Applied Surface Science, 2010

Research paper thumbnail of Fabrication of ZnO:Mn nanoparticles with organic shell in a highly alkaline aqueous environment

Applied Surface Science, 2011

Synthesis of undoped and Mn doped ZnO nanoparticles by an inclusive co precipitation method and i... more Synthesis of undoped and Mn doped ZnO nanoparticles by an inclusive co precipitation method and in situ capping with heteromultifunctional organic stabilizer mercaptosuccinic acid (MSA) in a core shell structure, in highly alkaline aqueous matrix have been accomplished. Near room temperature synthesis resulted in high quality monophasic wurtzite hexagonal structure of rod shaped nanoparticles of bare ZnO:Mn with no signature

Research paper thumbnail of Luminescence and high temperature ferromagnetism in YAlO nanophosphors: materials for efficient next generation LEDs and spintronic applications

RSC Advances, 2016

Yttrium-aluminium-oxide (YAlO) based nanophosphors for environment friendly and efficient white L... more Yttrium-aluminium-oxide (YAlO) based nanophosphors for environment friendly and efficient white LEDs and spintronics devices.

Research paper thumbnail of Lumino-magnetic YAG:Ce nanophosphors: novel synthesis routes for efficient luminescence and magnetic properties

J. Mater. Chem. C, 2014

Multifunctional lumino-magnetic YAG:Ce nanophosphors for LEDs and spintronics devices.

Research paper thumbnail of Electronic and luminescent characteristics of Aluminum doped ZnO nanocrystals

Electronic Materials Letters, 2015

donor levels and intrinsic acceptor centre. Both AZO samples exhibit n-type conduction with resis... more donor levels and intrinsic acceptor centre. Both AZO samples exhibit n-type conduction with resistivity of AZO prepared in inert (argon) ambient condition showing lower resistivity compared to the one synthesized in air atmosphere.

Research paper thumbnail of Fabrication of Luminescent, Magnetic Hollow Core Nanospheres and Nanotubes of Cr-Doped ZnO by Inclusive Coprecipitation Method 1

The Journal of Physical Chemistry C, 2010

... Chawla, S.; Jayanthi, K.; Kotnala, RK Phys. Rev. B 2009, 79, 125204 [CrossRef]. 18. Chawla, S... more ... Chawla, S.; Jayanthi, K.; Kotnala, RK Phys. Rev. B 2009, 79, 125204 [CrossRef]. 18. Chawla, S.; Jayanthi, K.; Kotnala, RK J. Appl. Phys. 2009, 106, 113923 [CrossRef]. 19. Sato, K.; Yoshida, HK Jpn. J. Appl. ... Venkatesan, M.; Fitzgerald, CB; Lunney, JG; Coey, JMD Phys. Rev. Lett. ...

Research paper thumbnail of Enhancement of luminescence in ZnMgO thin-film nanophosphors and application for white light generation

physica status solidi (a), 2008

Research paper thumbnail of Structure and luminescence of (Zn,Mg)O:Zn2+ nanophosphor films

Materials Letters, 2008

This article was published in an Elsevier journal. The attached copy is furnished to the author f... more This article was published in an Elsevier journal. The attached copy is furnished to the author for non-commercial research and education use, including for instruction at the author's institution, sharing with colleagues and providing to institution administration. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright

Research paper thumbnail of Observation of Nd3+visible line emission in ZnO : Nd3+prepared by a controlled reaction in the solid state

Journal of Physics D: Applied Physics, 2013

ABSTRACT Visible emission from ZnO is usually broadband and realizing line emission from rare ear... more ABSTRACT Visible emission from ZnO is usually broadband and realizing line emission from rare earth f–f transitions in ZnO at room temperature has proven to be difficult. A controlled solid-state reaction process with different standing times to synthesize rare earth doped (Nd 3+) zinc oxide (ZnO) has shown that sharp and intense line emission in the orange region (595 nm) could be realized under blue excitation, where both excitation and emission transitions occur between Nd 3+ levels situated intragap in ZnO. In addition, host-to-Nd 3+ energy transfer is also observed under band-to-band excitation. Incidentally, undoped ZnO synthesized by an identical process exhibits a broad green emission. Detailed characterization of the ZnO :Nd 3+ powder by x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, x-ray photoelectron spectroscopy, photoluminescence spectroscopy and time-resolved decay indicates a hexagonal phase with the presence of Nd 3+ in the ZnO lattice, forming spherical particles (∼200 nm) having a sharp visible emission with decay time in the microsecond range (9.60 µs). (Some figures may appear in colour only in the online journal)

Research paper thumbnail of Growth, microstructure, UV and orange pink emission from ZnO nanocones

Journal of Crystal Growth, 2008

ZnO nanocones are synthesized as freestanding powder as well as thin film by precipitation in a h... more ZnO nanocones are synthesized as freestanding powder as well as thin film by precipitation in a highly alkaline aqueous solution. X-ray diffraction demonstrated well-formed wurtzite crystal structure. The microstructure and morphology of individual nanocone were studied by transmission electron microscopy. Photoluminescence studies show strong UV emission in both powder and thin film form. Powder samples also show weak orange pink emission under UV excitation. High UV to visible emission ratio implies purity of the crystallites. However, the ZnO crystallites are also excitable by purple/blue light to emit in orange/red region and act as down conversion phosphor in the visible range indicating role of some intragap states. Fluorescence lifetime spectroscopy indicates fast recombination in hundreds of picoseconds range and complex charge transfer process in the microsecond range suggesting role of excitons and intragap states in the photophysical process.

Research paper thumbnail of Synthesis and optical properties of ZnO/MgO nanocomposite

Journal of Alloys and Compounds, 2008

... One of the authors (K. Jayanthi) is highly grateful to the Council of Scientific and Industri... more ... One of the authors (K. Jayanthi) is highly grateful to the Council of Scientific and Industrial Research (CSIR), India, for her fellowship under CSIR Diamond Jubilee Research Intern Scheme (No. ... [4] S. Choopun, RD Vispute, W. Yang, RP Sharma and T. Venkatesan, Appl. Phys. ...

Research paper thumbnail of Synthesis and surface modification of ZnO:Cu nanoparticles by silica and PMMA

Current Applied Physics, 2010

ZnO nanoparticles doped with Cu were synthesized by solid state reaction using different precurso... more ZnO nanoparticles doped with Cu were synthesized by solid state reaction using different precursor routes and varying growth environment. Average crystallite size varied from 40 to 100 nm depending upon synthesis temperature, lower temperature favouring smaller particle size. Scanning ...

Research paper thumbnail of Synthesis of Mn doped ZnO nanoparticles with biocompatible capping

Applied Surface Science, 2010

Research paper thumbnail of Fabrication of ZnO:Mn nanoparticles with organic shell in a highly alkaline aqueous environment

Applied Surface Science, 2011

Synthesis of undoped and Mn doped ZnO nanoparticles by an inclusive co precipitation method and i... more Synthesis of undoped and Mn doped ZnO nanoparticles by an inclusive co precipitation method and in situ capping with heteromultifunctional organic stabilizer mercaptosuccinic acid (MSA) in a core shell structure, in highly alkaline aqueous matrix have been accomplished. Near room temperature synthesis resulted in high quality monophasic wurtzite hexagonal structure of rod shaped nanoparticles of bare ZnO:Mn with no signature

Research paper thumbnail of Luminescence and high temperature ferromagnetism in YAlO nanophosphors: materials for efficient next generation LEDs and spintronic applications

RSC Advances, 2016

Yttrium-aluminium-oxide (YAlO) based nanophosphors for environment friendly and efficient white L... more Yttrium-aluminium-oxide (YAlO) based nanophosphors for environment friendly and efficient white LEDs and spintronics devices.