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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. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 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] [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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Diacon A, Rusen E, Mocanu A, Hudhomme P, Cincu C. Fluorescence properties of photonic crystals doped with perylenediimide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:7464-7470. [PMID: 21604771 DOI: 10.1021/la200878b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This study aims to present the fabrication of colloidal photonic crystals (PC) with increased fluorescence properties. The use of a highly fluorescent perylenediimide derivate (PDI) during the soap-free emulsion polymerization of styrene-acrylic acid resulted in monodisperse core-shell particles which allowed the fabrication of PC films. The properties of the hybrid material were studied in comparison with hybrid materials obtained by impregnation of films with chromophore solutions. In both cases an increase of the fluorescence response was observed in addition to a blue shift for the PDI core particles, proving the incorporation of the dye inside the copolymer particles.
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Affiliation(s)
- Aurel Diacon
- Department of Polymer Science, University Politehnica of Bucharest, 149 Calea Victoriei, RO-010072 Bucharest, Romania
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Yamada Y, Yamada H, Nakamura T, Yano K. Manipulation of the spontaneous emission in mesoporous synthetic opals impregnated with fluorescent guests. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:13599-13605. [PMID: 19642624 DOI: 10.1021/la901959f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The spontaneous emission of light from light-emitting materials adsorbed within the ordered pores of monodispersed mesoporous silica spheres (MMSS) has been investigated. By taking advantage of the ordered starburst pores of MMSS, we can provide a simple strategy for fabricating synthetic opals consisting of homogeneous individual building blocks in which fluorescent guests are uniformly and stably impregnated. In this study, tris(8-hydroxyquinolinato)aluminum(III) (Alq(3)) and Rhodamine B (Rh B) are selected as the fluorescent guests. The former has a wider emission band than the reflection spectrum of MMSS synthetic opals, whereas the emission band of the latter is considerably narrower than the reflection spectrum of the opals. The spontaneous emissions of these functionalized synthetic opals are clearly influenced by the stop band governed by the Bragg equation. In the case of the Alq(3)-MMSS conjugate, the shape of the Alq(3) emission spectrum varies in accordance with the shift in the stop band. The emission of the Rh B-MMSS conjugate is noticeably narrowed, and its intensity is enhanced when the excitation intensity is increased. These results are well explained by an inhibition of spontaneous emission caused by a reduction in the density of optical states within the stop band. The results of this study indicate that MMSS synthetic opals are promising for use in novel optical applications in which the spontaneous emission can be manipulated.
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Affiliation(s)
- Yuri Yamada
- Toyota Central Research & Development Laboratories., Inc., Nagakute, Aichi 480-1192, Japan.
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Yoo HS, Han JY, Kim SW, Jeon DY, Bae BS. Self-assembled SiO2 photonic crystal infiltrated by Ormosil:Eu(DBM)(3)phen phosphor and its enhanced photoluminescence. OPTICS EXPRESS 2009; 17:3732-3740. [PMID: 19259214 DOI: 10.1364/oe.17.003732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Luminescence films were prepared by infiltration of the tris(dibenzoylmethane) mono(1, 10-phenanthroline) europium incorporated ormosil into colloidal SiO(2) photonic crystal templates. Because a stopband of the template was not overlapped with the PL excitation and emission bands, the stopband did not suppress the PL intensity. The PL intensity of the infiltrated film into the template was about 13.1 times higher than that of the plane film prepared without the template. Three major terms, which are the mass term, the scattering term, and the crystallinity term, were considered as factors that improve the PL intensity. The relative ratio of the effects of the mass term : the scattering term : the crystallinity term was 2.1 : 2.8 : 2.2.
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Affiliation(s)
- Hyoung Sun Yoo
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea
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Nakamura T, Yamada Y, Yamada H, Yano K. A novel route to luminescent opals for controlling spontaneous emission. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b908822a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Silver J, Withnall R, Ireland TG, Fern GR, Zhang S. Light-emitting nanocasts formed from bio-templates: FESEM and cathodoluminescent imaging studies of butterfly scale replicas. NANOTECHNOLOGY 2008; 19:095302. [PMID: 21817666 DOI: 10.1088/0957-4484/19/9/095302] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Nanocasts comprising of red-light-emitting cubic Y(2)O(3):Eu phosphors were made from butterfly wing scale bio-templates. We report herein the first cathodoluminescent images made from such nanocasts and show that valuable insights into the nature of the internal structure of the casts can be gained by the use of this technique. The casts faithfully reproduced the fine sub-micrometre size detail of the scales, as was made evident by both FESEM and cathodoluminescent images that were collected from the same sample areas using a hyphenated FESEM-CL instrument. There was excellent agreement between the FESEM and cathodoluminescent images, the image quality of the latter indicating that the Eu(3+) activator ions were evenly dispersed in the Y(2)O(3):Eu phosphor on a sub-micrometre scale. The casts were made by infilling the natural moulds with a Y(2)O(3):Eu precursor solution that was subsequently dried and fired to convert it into the phosphor material. This method provides a simple, low cost route for fabricating nanostructures having feature dimensions as small as 20 nm in size, and it has the potential to be applied to other metal oxide systems for producing nano-and micro-components for electronic, magnetic or photonic integrated systems.
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