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Sasidhar N, Vidya YS, Manjunatha HC, Soundar R, Munirathnam R, Seenappa L, Sridhar KN, Manjunatha S, Krishnakanth E. Progress towards blue emitting MgO-ZnO-Ga 2O 3 nanocomposites synthesized by bio mediated route. Spectrochim Acta A Mol Biomol Spectrosc 2024; 310:123901. [PMID: 38262295 DOI: 10.1016/j.saa.2024.123901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/28/2023] [Accepted: 01/15/2024] [Indexed: 01/25/2024]
Abstract
MgO-ZnO-Ga2O3 nanocomposites are synthesized by solution combustion method using Aloe Vera gel as a reducing agent to increase the efficiency of blue emission. The appearance of Bragg reflections corresponding to MgO, ZnO and Ga2O3 clearly indicates the formation of nanocomposites. The surface morphology consists irregular shape and sized NPs. The Energy dispersive X-ray analysis confirms the purity of the sample. The band energy gap was tuned to 3.1 eV. The Photoluminescence excitation and emission spectra was discussed and compared it with emission spectra of individual oxides as well as with other reported blue emitted nanophosphors. Further, the chromaticity coordinates and Color correlated temperature coordinates clearly confirms their warm blue emission. Further, the powder dusting method was employed to collect the latent fingerprints on the pores and non-pores surfaces. The synthesized MgO-ZnO-Ga2O3 nanocomposites exhibits well-resolved ridge patterns that can be used to identify latent finger prints with clarity. From all these results, the present synthesized MgO-ZnO-Ga2O3 nanocomposite might find an application in display technology as a blue nanophosphor material and for latent finger print detection in crime investigation.
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Affiliation(s)
- N Sasidhar
- Department of Physics, Government science college, Chithradurga 577501, Karnataka, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastri Government First Grade College, RT Nagar, Bangalore 560032, Karnataka, India.
| | - H C Manjunatha
- Department of Physics, Government First Grade College, Devanahalli 562110, Karnataka, India.
| | - R Soundar
- Department of Physics, Government First Grade College, Devanahalli 562110, Karnataka, India
| | - R Munirathnam
- Department of Physics, Government First Grade College, Devanahalli 562110, Karnataka, India
| | - L Seenappa
- Department of Physics, Government First Grade College, Mulbagal 563131, Karnataka, India
| | - K N Sridhar
- Department of Physics, Government First Grade College, Malur 563130, Karnataka, India
| | - S Manjunatha
- Department of Chemistry, B.M.S College of Engineering, Bengaluru 560019, Karnataka, India
| | - E Krishnakanth
- Department of Physics, Government First Grade College, Devanahalli 562110, Karnataka, India
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Reddy BRC, Manjunatha HCS, Vidya YS, Sridhar KN, Seenappa L, Manjunatha S, Sathish KV, Munirathnam R, Nagaiah N. X-ray/gamma radiation shielding properties of zinc ferrite nanoparticles synthesised via solution combustion method. Radiat Prot Dosimetry 2023; 199:2506-2512. [PMID: 38126858 DOI: 10.1093/rpd/ncad224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 06/19/2023] [Accepted: 07/04/2023] [Indexed: 12/23/2023]
Abstract
Zinc ferrite (ZnFe2O4) nanoparticles were synthesised via solution combustion method using urea as a fuel. The synthesised samples were characterised with various techniques. The cubic structure with Fd-3 m space group is confirmed by Powder X-ray Diffraction and Bragg's reflection. The crystallite size estimated from Scherrer's method was found to be 40 nm. The agglomerated irregular shape and sized surface morphology was confirmed by Scanning Electron Microscopy image. The direct energy band gap determined from Wood and Tauc's relation was found to be 5.25 eV. Using a NaI (Tl) detector and multi-channel analyser, the described sample was examined for X-ray and gamma ray shielding characteristics in the energy range of 0.081-1.332 MeV. The measured shielding values are in good agreement with the theory, however below 356 keV, there is a little variation of up to 10%. The current work offers up new possibilities for using this simple, affordable, effective and low temperature approach to create nanomaterials for X-ray and gamma ray shielding.
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Affiliation(s)
- Byra R C Reddy
- Department of Physics, Presidency University, Bengaluru 560064, Karnataka, India
- Department of Physics, Government First Grade College, Srinivasapur 563135, Karnataka, India
| | | | - Yalekadakalu S Vidya
- Department of Physics, Lal Bahadur Shastri Government First Grade College, RT Nagar, Bangalore 560032, Karnataka, India
| | - K N Sridhar
- Department of Physics, Government First Grade College, Kolar 563101, Karnataka, India
| | - Lakshmaiah Seenappa
- Department of Physics, Government College for Women, Kolar 563101, Karnataka, India
| | - Shivanna Manjunatha
- Department of Chemistry, B.M.S. College of Engineering, Bengaluru 560019, Karnataka, India
| | | | | | - Ningaiah Nagaiah
- Department of Physics, Bangalore University, Bengaluru 560056, Karnataka, India
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Akshay S, Vidya YS, Manjunatha HC, Gurushantha K, Sridhar KN, Prashantha SC. Effect of Eu 3+ doping on structural and optical properties of zirconium titanate. Spectrochim Acta A Mol Biomol Spectrosc 2023; 301:123005. [PMID: 37327499 DOI: 10.1016/j.saa.2023.123005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/18/2023] [Accepted: 06/09/2023] [Indexed: 06/18/2023]
Abstract
The Europium activated (1-9 mol %) Zirconium Titanate nanoparticles (NPs) have been synthesized by the green solution combustion method using Aloe Vera gel extract as a reducing agent, followed by the calcination at 720 °C for 3hrs. All the synthesized samples crystallize in a pure orthorhombic crystal structure with the space group of Pbcn. The surface and bulk morphology were analyzed. The crystallite size increases, whereas the direct energy band gap was found to decrease with an increase in dopant concentration. Further, the effect of dopant concentration on the photoluminescence properties was studied. The presence of Eu3+ ion in the trivalent state in the host lattice was confirmed by its characteristic emission at 610 nm due to 5D0→7F2 (λex = 464 nm). The CIE coordinates were found in the red region of the CIE 1931 diagram. The CCT coordinates lie in the range 6288-7125 K. The Judd-Ofelt parameters and derived quantities were analyzed. This theory confirms the high symmetry of Eu3+ ions in the host lattice. These findings imply that ZTO:Eu3+ can be employed as a nanopowder material in a red-emitting phosphor material.
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Affiliation(s)
- S Akshay
- Department of Physics, Maharani Lakshmi Ammanni College for Women, Autonomous Malleshwaram, Bengaluru 560012, Karnataka, India; Department of Physics, East West Institute of Technology, Bengaluru 560091, Karnataka, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastri Government First Grade College, RT Nagar, Bangalore 560032, Karnataka, India.
| | - H C Manjunatha
- Department of Physics, Government College for Women, Kolar 563101, Karnataka, India.
| | - K Gurushantha
- Department of Chemistry, M S Ramaiah Institute of Technology (affiliated to Visvesvaraya Technological University, Belguam, Bengaluru 560054, Karnataka, India
| | - K N Sridhar
- Department of Physics, Government First Grade College, Kolar 563101, Karnataka, India
| | - S C Prashantha
- Department of Physics, East West Institute of Technology, Bengaluru 560091, Karnataka, India.
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Srinath NR, Manjunatha HC, Vidya YS, Munirathnam R, Sridhar KN, Manjunatha S, Krishnakanth E. Red emission of copper aluminate synthesized via chemical and bio-mediated routes. RSC Adv 2023; 13:17508-17515. [PMID: 37304809 PMCID: PMC10253492 DOI: 10.1039/d3ra01969a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 05/20/2023] [Indexed: 06/13/2023] Open
Abstract
For the first time, copper aluminate nanoparticles (NPs) are synthesized by a combustion method using urea as a fuel (CAOU) and Ocimum sanctum (tulsi) extract as a reducing agent (CAOT). The Bragg reflections of the as-formed product confirm the formation of a cubic phase with Fd3̄m space group. The crystallite size, crystallinity and other structural parameters are discussed. The surface morphology of CAOU is agglomerated in nature whereas that of CAOT is hexagonal in shape. The smaller crystallite size CAOT NPs show a higher energy band gap. The photoluminescence (PL) analysis excited at 302 nm shows that the CIE coordinates fall in the red region. The oxygen defects are mainly responsible for the PL emission. The CCT coordinates confirm that both CAOU and CAOT NPs can find an application in warm light emitting diodes.
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Affiliation(s)
- N R Srinath
- Department of Physics, Government College for Women Kolar-563101 Karnataka India
| | - H C Manjunatha
- Department of Physics, Government College for Women Kolar-563101 Karnataka India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastri Government First Grade College RT Nagar Bangalore-560032 Karnataka India
| | - R Munirathnam
- Department of Physics, Government College for Women Kolar-563101 Karnataka India
| | - K N Sridhar
- Department of Physics, Government First Grade College Kolar-563101 Karnataka India
| | - S Manjunatha
- Department of Chemistry, B.M.S College of Engineering Bengaluru-560019 Karnataka India
| | - E Krishnakanth
- Department of Physics, Government College for Women Kolar-563101 Karnataka India
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S A, Vidya YS, Manjunatha HC, Prashantha SC, Kottam N, Sridhar KN, Damodara Gupta PS, Mahendrakumar C. Photoluminescence, antibacterial, X-ray/gamma ray absorption, supercapacitor and sensor applications of ZrTiO 4 nanorods. RSC Adv 2023; 13:14782-14796. [PMID: 37197183 PMCID: PMC10184272 DOI: 10.1039/d3ra00908d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 04/13/2023] [Indexed: 05/19/2023] Open
Abstract
In the present communication, ZrTiO4 nanoparticles (NPs) are synthesized by the solution combustion method using urea (ZTOU) and oxalyl dihydrazide (ODH) (ZTODH) as fuel and calcined at 700 °C. The synthesized samples were characterized with different techniques. Powder X-ray diffraction studies show the presence of diffraction peaks corresponding to ZrTiO4. In addition to these peaks, a few additional peaks corresponding to the monoclinic and cubic phases of ZrO2 and the rutile phase of TiO2 are observed. The surface morphology of ZTOU and ZTODH consists of nanorods with different lengths. The TEM and HRTEM images confirm the formation of nanorods along with NPs, and the estimated crystallite size matches well with that of PXRD. The direct energy band gap was calculated using Wood and Tauc's relation and was found to be 2.7 and 3.2 eV for ZTOU and ZTODH respectively. The photoluminescence emission peaks (λ = 350 nm), CIE and CCT of ZTOU and ZTODH clearly confirm that the present nanophosphor might be a good nanophosphor material for blue or aqua green light emitting diodes. Furthermore, antibacterial activity and a viability test were conducted on two food borne pathogens. The X-ray/gamma ray absorption properties are also studied, which clearly show the ZrTiO4 might be a good absorbing material. Furthermore, cyclic voltammetry (CV) analysis of ZTOU nanorods shows very good redox peaks compared to that of ZTODH. From the electrochemical impedance spectroscopy (EIS) measurements, the charge-transfer resistances for prepared nanorods ZTOU and ZTODH are found to be 151.6 Ω, and 184.5 Ω respectively. The modified graphite electrode with ZTOU shows good sensing activity for both paracetamol and ascorbic acid, compared to ZTODH.
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Affiliation(s)
- Akshay S
- Department of Physics, Maharani Lakshmi Ammanni College for Women Autonomous Malleshwaram Bengaluru 560012 Karnataka India
- Department of Physics, East West Institute of Technology Bengaluru 560091 Karnataka India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastri Government First Grade College RT Nagar Bangalore 560032 Karnataka India
| | - H C Manjunatha
- Department of Physics, Government College for Women Kolar 563101 Karnataka India
| | - S C Prashantha
- Department of Physics, East West Institute of Technology Bengaluru 560091 Karnataka India
| | - Nagaraju Kottam
- Department of Chemistry, M S Ramaiah Institute of Technology affiliated to Visvesvaraya Technological University Belguam Bengaluru 560054 Karnataka India
| | - K N Sridhar
- Department of Physics, Government First Grade College Kolar 563101 Karnataka India
| | - P S Damodara Gupta
- Department of Physics, Government College for Women Kolar 563101 Karnataka India
| | - C Mahendrakumar
- Department of Biotechnology, Government First Grade College Kolar 563101 Karnataka India
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Prasanna Kumar JB, Ramgopal G, Sunitha DV, Prasad BD, Nagabhushana H, Vidya YS, Anantharaju KS, Prashantha SC, Sharma SC, Prabhakara KR. Extraction of Y 2 O 3 :Cr 3+ nanophosphor by eco-friendly approach and its suitability for white light-emitting diode applications. LUMINESCENCE 2016; 32:414-424. [PMID: 27620118 DOI: 10.1002/bio.3197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 05/23/2016] [Accepted: 07/11/2016] [Indexed: 11/11/2022]
Abstract
Cr3+ -doped Y2 O3 (0.5-9 mol%) was synthesized by a simple solution combustion method using Aloe vera gel as a fuel/surfactant. The final obtained product was calcined at 750°C for 3 h, which is the lowest temperature reported so far for the synthesis of this compound. The calcined product was confirmed for its crystallinity and purity by powder X-ray diffraction (PXRD) studies which showed a single-phase nano cubic phosphor. The particles size estimated by Scherrer formula was in the range of 6-19 nm. The UV-vis spectra showed absorption bands at 198, 272 and 372 nm having band gap energy in the range 4.00-4.26 eV. In order to investigate the possibility of its use in white light emitting display applications, the photoluminescence properties of Cr3+ -doped Y2 O3 nanophosphors were studied at an excitation wavelength in the near ultraviolet (UV) light region (361 nm). The emission spectra consisted of emission peaks in the blue (4 F9/2 → 6 H15/2 ), orange (4 F9/2 → 6 H13/2 ) and red (4 F9/2 → 6 H11/2 ) regions. The CIE coordinates (0.33, 0.33) lie in the white light region. Hence Y2 O3 :Cr3+ can be used for white light-emitting diode (LED) applications.
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Affiliation(s)
- J B Prasanna Kumar
- Department of Physics, GFGC Tumkur, Tumkur, 572 102, Karnataka, India.,Department of Physics, Sathyabama University, Chennai, 600 119, Tamilnadu, India
| | - G Ramgopal
- Department of Physics, Maharani's Science College, Palace Road, Bangalore, 560 001, India
| | - D V Sunitha
- School of Physical sciences, REVA University, Bangalore, 560 064, Karnataka, India
| | - B Daruka Prasad
- Department of Physics, B.M.S. Institute of Technology, VTU Belagavi affiliated, Bangalore, 560064, India
| | - H Nagabhushana
- CNR Rao Centre for Advanced Materials, Tumkur University, Tumkur, 572103, India
| | - Y S Vidya
- Department of Physics, Lalbahadur Shastry Govt., First Grade College, Bangalore, 560 032, India
| | - K S Anantharaju
- Dayanand Sagar University, Shavige Malleshwara Hills, Kumaraswamy Layout, Bangalore, 560 078, India
| | - S C Prashantha
- Research Centre, Department of Science, East West Institute of Technology, Bangalore, 560 091, India
| | - S C Sharma
- Dayanand Sagar University, Shavige Malleshwara Hills, Kumaraswamy Layout, Bangalore, 560 078, India
| | - K R Prabhakara
- Department of Mechanical Engineering, R. V. College of Engineering, Bangalore, 560 059, India
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Madan HR, Sharma SC, Suresh D, Vidya YS, Nagabhushana H, Rajanaik H, Anantharaju KS, Prashantha SC, Sadananda Maiya P. Facile green fabrication of nanostructure ZnO plates, bullets, flower, prismatic tip, closed pine cone: Their antibacterial, antioxidant, photoluminescent and photocatalytic properties. Spectrochim Acta A Mol Biomol Spectrosc 2016; 152:404-16. [PMID: 26241826 DOI: 10.1016/j.saa.2015.07.067] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 07/12/2015] [Accepted: 07/13/2015] [Indexed: 05/27/2023]
Abstract
Green synthesis of multifunctional Zinc oxide nanoparticles (NPs) with a variety of morphologies were achieved by low temperature solution combustion route employing neem (Azadirachta indica) extract as fuel. The nanoparticles were characterized by PXRD, FTIR, XPS, Raman and UV-Visible spectroscopic studies. The Morphologies were studied by SEM and TEM analysis. The NPs were subjected for photoluminescence, photocatalytic, antibacterial and antioxidant activity studies. PXRD pattern confirmed the hexagonal wurtzite structure of the product. SEM images indicated the transformation of mushroom like hexagonal disks to bullets, buds, cones, bundles and closed pine cone structured NPs with increase in the concentration of neem extract in reaction mixture. The NPs exhibited prominent green emission due to the presence of intrinsic defect centers. The as-formed bullet shaped ZnO with 4ml of neem extract was found to decolorize Methylene blue (MB) under Sunlight and UV light irradiation. The antibacterial studies indicated that ZnO NPs of concentration 500, 750 and 1000μg resulted in significant antibacterial activity on Klebsiella aerogenes and Staphylococcus aureus but not against Escherichia coli and Pseudomonas aeruginosa in agar well diffusion method. Further, ZnO NPs exhibited significant antioxidant activity against scavenging DPPH free radicals. The current investigation demonstrated green engineering method for the synthesis of multifunctional ZnO NPs with interesting morphologies using neem extract.
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Affiliation(s)
- H R Madan
- Department of Electronics, Tumkur University, Tumkur 572 103, India
| | - S C Sharma
- Dayananda Sagar University, Shavige Malleshwara Hills, Kumaraswamy layout, Bangalore 560078, Karnataka, India
| | - D Suresh
- Department of Studies & Research in Chemistry, Tumkur University, Tumkur 572 103, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - H Nagabhushana
- Prof. C.N.R. Rao Centre for Advanced Materials Research, Tumkur University, Tumkur 572 103, India.
| | - H Rajanaik
- Department of Studies and Research in Environmental Science, Tumkur University, Tumkur 572 103, India
| | - K S Anantharaju
- Department of Chemistry, Dayananda Sagar College of Engineering, Shavige Malleshwara Hills, Kumaraswamy layout, Bangalore 560078, Karnataka, India.
| | - S C Prashantha
- Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - P Sadananda Maiya
- Dr. P. Sadananda Maiya Center for Food Science Research, 4th Block, Jayanagara, Bangalore 560 011, India
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Prasannakumar JB, Vidya YS, Anantharaju KS, Ramgopal G, Nagabhushana H, Sharma SC, Daruka Prasad B, Prashantha SC, Basavaraj RB, Rajanaik H, Lingaraju K, Prabhakara KR, Nagaswarupa HP. Bio-mediated route for the synthesis of shape tunable Y₂O₃: Tb³⁺ nanoparticles: Photoluminescence and antibacterial properties. Spectrochim Acta A Mol Biomol Spectrosc 2015; 151:131-140. [PMID: 26125993 DOI: 10.1016/j.saa.2015.06.081] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 06/20/2015] [Accepted: 06/23/2015] [Indexed: 06/04/2023]
Abstract
The study reports green mediated combustion route for the synthesis of Tb(3+) ion activated Y2O3 nanophosphors using Aloe Vera gel as fuel. The concentration of Tb(3+) plays a key role in controlling the morphology of Y2O3 nanostructures. The formation of different morphologies of Y2O3: Tb(3+) nanophosphors were characterized by PXRD, SEM, TEM and HRTEM. PXRD data and Rietveld analysis evident the formation of single phase Y2O3 with cubic crystal structure. The influence of Tb(3+) ion concentration on structural morphology, UV-visible absorption and PL emission were investigated systematically. The PL emission of Y2O3: Tb(3+) (1-11 mol%) nanophosphors were studied in detail under 271 and 304nm excitation wavelengths. The CIE coordinates lies well within green region and correlated color temperature values were found to be 6221 and 5562K under different excitations. Thus, the present phosphor can serve as an excellent candidate for LEDs. Further, prismatic Y2O3: Tb(3+) (3 mol%) nanophosphor showed significant antibacterial activity against Pseudomonas desmolyticum and Staphylococcus aureus. The present study successfully demonstrates Y2O3: Tb(3+) nanophosphors can be used for display applications as well as in medical applications for controlling pathogenic bacteria.
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Affiliation(s)
- J B Prasannakumar
- Department of Physics, GFGC Tumkur, Tumkur 572 102, Karnataka, India; Department of Physics, Sathyabama University, Jeppiaar Nagar, Chennai 600 119, Tamilnadu, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - K S Anantharaju
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - G Ramgopal
- Department of Physics, Maharani's Science College, Palace Road, Bangalore 560 001, Karnataka, India
| | - H Nagabhushana
- CNR Rao Centre for Advanced Materials, Tumkur University, Tumkur 572103, India.
| | - S C Sharma
- Dayananda Sagar University, Shavige Malleshwara Hills, Kumaraswamy Layout, Bangalore 560078, Karnataka, India
| | - B Daruka Prasad
- Department of Physics, B M S Institute of Technology, Yelahanka, Bangalore 560064, India
| | - S C Prashantha
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - R B Basavaraj
- CNR Rao Centre for Advanced Materials, Tumkur University, Tumkur 572103, India
| | - H Rajanaik
- Department of Studies and Research in Environmental Science, Tumkur University, Tumkur 572 103, India
| | - K Lingaraju
- Department of Studies and Research in Environmental Science, Tumkur University, Tumkur 572 103, India
| | - K R Prabhakara
- Department of Mechanical Engineering, R.V. College of Engineering, Bangalore 560059, India
| | - H P Nagaswarupa
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
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Anilkumar MR, Nagaswarupa HP, Nagabhushana H, Sharma SC, Vidya YS, Anantharaju KS, Prashantha SC, Shivakuamra C, Gurushantha K. Bio-inspired route for the synthesis of spherical shaped MgO:Fe(3+) nanoparticles: Structural, photoluminescence and photocatalytic investigation. Spectrochim Acta A Mol Biomol Spectrosc 2015; 149:703-713. [PMID: 25988816 DOI: 10.1016/j.saa.2015.05.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 04/20/2015] [Accepted: 05/04/2015] [Indexed: 06/04/2023]
Abstract
MgO:Fe(3+) (0.1-5 mol%) nanoparticles (NPs) were synthesized via eco-friendly, inexpensive and simple low temperature solution combustion route using Aloe vera gel as fuel. The final products were characterized by SEM, TEM and HRTEM. PXRD data and Rietveld analysis revealed the formation of cubic system. The influence of Fe(3+) ion concentration on the structure morphology, UV absorption, PL emission and photocatalytic activity of MgO:Fe(3+) NPs were investigated. The yellow emission with CIE chromaticity coordinates (0.44, 0.52) and average correlated color temperature value was found to be 3540 K which corresponds to warm light of NPs. The control of Fe(3+) on MgO matrix influences the photocatalytic decolorization of methylene blue (MB) under UV light. The enhanced photocatalytic activity of MgO:Fe(3+) (4 mol%) was attributed to dopant concentration, effective crystallite size, textural properties, decreased band gap and capability for reducing the electron-hole pair recombination. Further, the trends of inhibitory effect in the presence of different radical scavengers were explored. These findings open up new avenues for the exploration of Fe-doped MgO in eco-friendly water applications and in the process of display devices.
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Affiliation(s)
- M R Anilkumar
- Department of Science, Research Center, East West Institute of Technology, Bangalore 560 091, India
| | - H P Nagaswarupa
- Department of Science, Research Center, East West Institute of Technology, Bangalore 560 091, India.
| | - H Nagabhushana
- Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India
| | - S C Sharma
- Dayananda Sagar University, Shavige Malleshwara Hills, Kumaraswamy Layout, Bangalore 560078, Karnataka, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - K S Anantharaju
- Department of Science, Research Center, East West Institute of Technology, Bangalore 560 091, India.
| | - S C Prashantha
- Department of Science, Research Center, East West Institute of Technology, Bangalore 560 091, India
| | - C Shivakuamra
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India
| | - K Gurushantha
- Department of Science, Research Center, East West Institute of Technology, Bangalore 560 091, India
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10
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Prasanna Kumar JB, Ramgopal G, Vidya YS, Anantharaju KS, Daruka Prasad B, Sharma SC, Prashantha SC, Nagaswarupa HP, Kavyashree D, Nagabhushana H. Green synthesis of Y2O3:Dy(3+) nanophosphor with enhanced photocatalytic activity. Spectrochim Acta A Mol Biomol Spectrosc 2015; 149:687-697. [PMID: 25985135 DOI: 10.1016/j.saa.2015.05.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 04/25/2015] [Accepted: 05/04/2015] [Indexed: 06/04/2023]
Abstract
Facile and green route was employed for the synthesis of Y2O3:Dy(3+) (1-11 mol%) nanostructures (NSs) using Aloe vera gel as fuel. The formation of different morphologies of Y2O3:Dy(3+) NSs were characterized by SEM, TEM and HRTEM. PXRD data and Rietveld analysis evident the formation of single phase Y2O3 with cubic crystal structure. The influence of Dy(3+) ion concentration on the structure morphology, UV absorption, PL emission and photocatalytic activity of NSs were investigated. NSs exhibited an intense warm white emission with CIE chromaticity coordinates (0.32, 0.33) and average CCT value ∼5525 K which corresponds to vertical day light. The control of Dy(3+) ion on Y2O3 matrix influences the photocatalytic decolorization of Metanil Yellow as a model compound was evaluated. The enhanced photocatalytic activities of core shell structured Y2O3:Dy(3+) (1 mol%) was attributed to co-operation effect of dopant concentration, crystallite size, textural properties and capability for reducing electron-hole pair recombination. Further, the recycling catalytic ability of Y2O3:Dy(3+) (1 mol%) nanostructure was also evaluated and found promising photocatalytic performance with negligible decrease in decolorization efficiency even after sixth successive cyclic runs. Considering its green, facile synthesis and recyclable feature from an aqueous solution, the present Y2O3:Dy(3+) (1 mol%) nanophosphor can be considered as one of the ideal photocatalyst for various potential applications.
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Affiliation(s)
- J B Prasanna Kumar
- Department of Physics, GFGC Tumkur, Tumkur 572 102, Karnataka, India; Department of Physics, Sathyabama University, Jeppiaar Nagar, Chennai 600 119, Tamilmadu, India
| | - G Ramgopal
- Department of Physics, Maharani's Science College, Palace Road, Bangalore 560 001, Karnataka, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - K S Anantharaju
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - B Daruka Prasad
- Department of Physics, B.M.S. Institute of Technology, Yelahanka, Bangalore 560 064, India
| | - S C Sharma
- Dayananda Sagar University, Shavige Malleshwara Hills, Kumara Swamy Layout, Bangalore 560 078, India
| | - S C Prashantha
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - H P Nagaswarupa
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - D Kavyashree
- Department of Physics, Channabasaveshwara Institute of Technology, B.H. Road, Gubbi, Tumkur 572 216, India
| | - H Nagabhushana
- Prof. CNR Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
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Malleshappa J, Nagabhushana H, Sharma SC, Vidya YS, Anantharaju KS, Prashantha SC, Daruka Prasad B, Raja Naika H, Lingaraju K, Surendra BS. Leucas aspera mediated multifunctional CeO2 nanoparticles: Structural, photoluminescent, photocatalytic and antibacterial properties. Spectrochim Acta A Mol Biomol Spectrosc 2015; 149:452-462. [PMID: 25978012 DOI: 10.1016/j.saa.2015.04.073] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 03/02/2015] [Accepted: 04/22/2015] [Indexed: 06/04/2023]
Abstract
Spherical shaped cerium dioxide (CeO2) nanoparticles (NPs) were synthesized via bio mediated route using Leucas aspera (LA) leaf extract. The NPs were characterized by PXRD, SEM, UV-Visible techniques. Photoluminescence (PL), photocatalysis and antibacterial properties of NPs were studied. PXRD patterns and Rietveld analysis confirm cubic fluorite structure with space group Fm-3m. SEM results evident that morphology of the NPs was greatly influenced by the concentration of LA leaf extract in the reaction mixture. The band gap energy of the NPs was found to be in the range of 2.98-3.4 eV. The photocatalytic activity of NPs was evaluated by decolorization of Rhodamine-B (RhB) under UVA and Sun light irradiation. CeO2 NPs show intense blue emission with CIE coordinates (0.14, 0.22) and average color coordinated temperature value ∼148,953 K. Therefore the present NPs quite useful for cool LEDs. The superior photocatalytic activity was observed for CeO2 NPs with 20 ml LA under both UVA and Sunlight irradiation. The enhanced photocatalytic activity and photoluminescent properties were attributed to defect induced band gap engineered CeO2 NPs. Further, CeO2 with 20 ml LA exhibit significant antibacterial activity against Escherichia coli (EC) and Staphylococcus aureus (SA). These findings show great promise of CeO2 NPs as multifunctional material for various applications.
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Affiliation(s)
- J Malleshappa
- Department of Physics, University College of Science, Tumkur University, Tumkur 572 103, India
| | - H Nagabhushana
- Prof. C.N.R. Rao Centre for Advanced Materials Research, Tumkur University, Tumkur 572 103, India.
| | - S C Sharma
- Dayananda Sagar University, Shavige Malleshwara hills Kumara swamy layout, Bangalore 560078, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India
| | - K S Anantharaju
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - S C Prashantha
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - B Daruka Prasad
- B.S. Narayan Centre of Excellence for Advanced Materials, B.M.S. Institute of Technology, Yelahanka, Bangalore 560 064, India
| | - H Raja Naika
- Department of Studies and Research in Environmental Science, Tumkur University, Tumkur 572 103, India
| | - K Lingaraju
- Department of Studies and Research in Environmental Science, Tumkur University, Tumkur 572 103, India
| | - B S Surendra
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
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Prasanna kumar JB, Ramgopal G, Vidya YS, Anantharaju KS, Daruka Prasad B, Sharma SC, Prashantha SC, Premkumar HB, Nagabhushana H. Bio-inspired synthesis of Y2O3: Eu(3+) red nanophosphor for eco-friendly photocatalysis. Spectrochim Acta A Mol Biomol Spectrosc 2015; 141:149-160. [PMID: 25668696 DOI: 10.1016/j.saa.2015.01.055] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 12/31/2014] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
We report the synthesis of Y2O3: Eu(3+) (1-11 mol%) nanoparticles (NPs) with different morphologies via eco-friendly, inexpensive and simple low temperature solution combustion method using Aloe Vera gel as fuel. The formation of different morphologies of Y2O3: Eu(3+) NPs were characterized by PXRD, SEM, TEM, HRTEM, UV-Visible and PL techniques. The PXRD data and Rietveld analysis confirms the formation of single phase Y2O3 with cubic crystal structure. The influence of Eu(3+) ion concentration on the morphology, UV-Visible absorption, PL emission and photocatalytic activity of Y2O3: Eu(3+) nanostructures were investigated. Y2O3: Eu(3+) NPs exhibit intense red emission with CIE chromaticity coordinates (0.50, 0.47) and correlated color temperature values at different excitation ranges from 1868 to 2600 K. The control of Eu(3+) ion on Y2O3 matrix influences the photocatalytic decolorization of methylene blue (MB) as a model compound was evaluated under UVA light. Enhanced photocatalytic activity of conical shaped Y2O3: Eu(3+) (1 mol%) was attributed to dopant concentration, crystallite size, textural properties and capability of reducing the electron-hole pair recombination. The trend of inhibitory effect in the presence of different radical scavengers followed the order SO4(2-)>Cl(-)>C2H5OH>HCO3(-)>CO3(2-). These findings show great promise of Y2O3: Eu(3+) NPs as a red phosphor in warm white LEDs as well as eco-friendly heterogeneous photocatalysis.
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Affiliation(s)
- J B Prasanna kumar
- Department of Physics, GFGC Tumkur, Tumkur 572 102, Karnataka, India; Department of Physics, Sathyabama University, Jeppiaar Nagar, Chennai 600 119, Tamilnadu, India
| | - G Ramgopal
- Department of Physics, Maharani's Science College, Palace Road, Bangalore 560 001, Karnataka, India
| | - Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - K S Anantharaju
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India.
| | - B Daruka Prasad
- Department of Physics, B M S Institute of Technology, Yelahanka, Bangalore 560064, India
| | - S C Sharma
- Chattisgarh Swami Vivekananda Technical University, Bhilai (CG) 493441, India
| | - S C Prashantha
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - H B Premkumar
- Department of Physics, Acharya Institute of Technology, Bangalore 560 090, India
| | - H Nagabhushana
- Prof. CNR Rao Centre for Advanced Materials, Tumkur University, Tumkur 572103, India.
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Ravikumar BS, Nagabhushana H, Sharma SC, Vidya YS, Anantharaju KS. Calotropis procera mediated combustion synthesis of ZnAl2O4:Cr(3+) nanophosphors: structural and luminescence studies. Spectrochim Acta A Mol Biomol Spectrosc 2015; 136 Pt B:1027-1037. [PMID: 25459629 DOI: 10.1016/j.saa.2014.09.126] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 09/21/2014] [Accepted: 09/25/2014] [Indexed: 06/04/2023]
Abstract
ZnAl2O4:Cr(3+) nanophosphors were synthesized for the first time by a simple and environment friendly route using Calotropis procera milk latex as fuel. The structural and surface morphological studies were carried out using powder X-ray diffraction (PXRD), scanning electron microscopy and transmission electron microscopy techniques. The photoluminescence (PL) properties of ZnAl2O4:Cr(3+) as a function of dopant concentration and calcination temperature was studied in detail. The PXRD patterns and Rietveld confinement confirmed the cubic crystal system with space group Fd-3m. The crystallite size estimated from Scherrer's and W-H plots was found to be in the range of 16-26 nm. The PL spectrum shows an intense peak at ∼688 and ∼699 nm assigned to spin-forbidden (2)Eg→(4)A2g transition of Cr(3+) ions. The PL measurements for two excitations (∼410 and 527 nm) and with respect to calcination temperature indicated no significant change in the shape and position of emission peak except PL intensity. The CIE chromaticity coordinates lies well within the white region. Thermoluminescence (TL) studies revealed well resolved glow peak at ∼212°C with a small shoulder at 188 and 233°C. The glow peak intensity at ∼212°C increases linearly with γ-dose which suggest ZnAl2O4:Cr(3+) is suitable candidate for radiation dosimetric applications. The activation energy (E in eV), order of kinetics (b) and Frequency factor (s) were estimated using glow peak shape method.
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Affiliation(s)
- B S Ravikumar
- C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India
| | - H Nagabhushana
- C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
| | - S C Sharma
- Chhattisgarh Swami Vivekananda Technical University, North Park Avenue, Sector-8, Bhilai, Chhattisgarh 490 009, India
| | - Y S Vidya
- Department of Physics, LBSGFGC, Bangalore 560 032, India
| | - K S Anantharaju
- Research Center, Department of Chemistry, East West Institute of Technology, Bangalore 560 091, India
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14
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Vidya YS, Anantharaju KS, Nagabhushana H, Sharma SC, Nagaswarupa HP, Prashantha SC, Shivakumara C. Combustion synthesized tetragonal ZrO2: Eu(3+) nanophosphors: structural and photoluminescence studies. Spectrochim Acta A Mol Biomol Spectrosc 2015; 135:241-251. [PMID: 25068837 DOI: 10.1016/j.saa.2014.06.151] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/15/2014] [Accepted: 06/29/2014] [Indexed: 06/03/2023]
Abstract
Novel crystalline tetragonal ZrO2: Eu(3+) phosphors were prepared by a facile and efficient low temperature solution combustion method at 400±10 °C using oxalyl dihydrazide (ODH) as fuel. The powder X-ray diffraction patterns and Rietveld confinement of as formed ZrO2: Eu(3+) (1-11 mol%) confirmed the presence of body centered tetragonal phase. The crystallite size estimated from Scherrer's and W-H plots was found to be in the range of 7-17 nm. These results were in good agreement with transmission electron microscopy studies. The calculated microstrain in most of the planes indicated the presence of tensile stress along various planes of the particles. The observed space group (P42/nmc) revealed the presence of cations in the 2b positions (0.75, 0.25, 0.25) and the anions in the 4d positions (0.25, 0.25, 0.45). The optical band gap energies estimated from Wood and Tauc's relation was found to be in the range 4.3-4.7 eV. Photoluminescence (PL) emission was recorded under 394 and 464 nm excitation shows an intense emission peak at 605 nm along with other emission peaks at 537, 592, 605 and 713 nm. These emission peaks were attributed to the transition of (5)D0→(7)FJ (J=0, 1, 2, 3) of Eu(3+) ions. The high ratio of Intensity of ((5)D0→(7)F2) and ((5)D0→(7)F1) infers that Eu(3+) occupies sites with a low symmetry and without an inversion center. CIE color coordinates indicated the red regions which could meet the needs of illumination devices.
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Affiliation(s)
- Y S Vidya
- Department of Physics, Lal Bahadur Shastry Government First Grade College, Bangalore 560 032, India.
| | - K S Anantharaju
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India.
| | - H Nagabhushana
- Prof. C.N.R. Rao Centre for Advanced Materials Research, Tumkur University, Tumkur 572 103, India
| | - S C Sharma
- Vice Chancellor, Chhattisgarh Swami Vivekananda Technical University, North Park Avenue, Sector-8, Bhilai, Chhattisgarh 490 009, India
| | - H P Nagaswarupa
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - S C Prashantha
- Research Center, Department of Science, East West Institute of Technology, Bangalore 560 091, India
| | - C Shivakumara
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India
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