Effect of Co doping, capping agent and optical-structural studies of ZnO:Co2+ nanoparticles
Faculty of Science, Majlesi Branch, Islamic Azad University, Isfahan, Islamic Republic of Iran
a e-mail: smt.Otaqsara@gmail.com
Revised: 28 March 2011
Accepted: 4 April 2011
Published online: 11 August 2011
Co2+ doped ZnO nanoparticles (NPs) using PEG as a capping agent were prepared by colloidal wet-chemical method. The structure, morphology and characteristics of as-prepared samples were investigated. X-ray diffraction patterns studies revealed wurtzite crystal phase. STM-TEM micrographs show a spherical shape and nearly well distribution with an average particle size of ~15–20 nm. UV-VIS spectra show the presence of exciton peak at 349 nm which can be effectively tuned versus cobalt doping and PEG concentration. PL studies were done under the excitation of 347 nm, which exhibited a UV (~386 nm) and visible (blue-orange) emission peak because of free-exciton recombination and oxygen vacancy.
© EDP Sciences, 2011