Optical properties of ZnO nanoparticles synthesized by varying the sodium hydroxide to zinc acetate molar ratios using a Sol-Gel process

• Autorzy: Francis Dejene , Abdub Ali , Hendrik Swart , Reinhardt Botha , Kittesa Roro , Liza Coetsee , Mart Biggs
• Języki publikacji: EN

Abstrakty

EN

Material property dependence on the OH−/Zn2+ molar ratio of the precursor was investigated by varying the amount of NaOH during synthesis of ZnO. It was necessary to control the water content and temperature of the mixture to ensure the reproducibility. It was observed that the structural properties, particle size, photoluminescence intensity and wavelength of maximum intensity were influenced by the molar ratio of the precursor. The XRD spectra for ZnO nanoparticles show the entire peaks corresponding to the various planes of wurtzite ZnO, indicating a single phase. UV measurements show the absorption that comes from the ZnO nanoparticles in visible region. The absorption edge of these ZnO nanoparticles are shifted to higher energies and the determined band gap energies are blue shifted as the OH−/Zn2 molar ration increases, due to the quantum confinement effects. The photoluminescence characterization of the ZnO nanostructures exhibited a broad emission band centred at green (600 nm) region for all molar ratios except for OH−/Zn2+ = 1.7 where a second blue emission around 468 nm was also observed. The photoluminescence properties of ZnO nanoparticles were largely determined by the size and surface properties of the nanoparticles.

Słowa kluczowe

EN

nanomaterials; semiconductor; NaOH molar ratio; ZnO: luminescence

• Czasopismo: Open Physics
• Rocznik: 2011
• Tom: 9
• Numer: 5
• Strony: 1321-1326

Daty

wydano

2011-10-01

online

2011-09-15

Twórcy

autor

Francis Dejene

• Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba, 9866, South Africa,

autor

Abdub Ali

• Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba, 9866, South Africa

autor

Hendrik Swart

• Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa

autor

Reinhardt Botha

• Department of Physics, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth, 6031, South Africa

autor

Kittesa Roro

• Department of Physics, Physics Department, University of Pretoria, Lynnwood Road, Pretoria, 0002, South Africa

autor

Liza Coetsee

• Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa

autor

Mart Biggs

• Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa

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Identyfikatory

DOI

10.2478/s11534-011-0050-3