The effect of Ce3+ on structure, morphology and optical properties of flower-like ZnO synthesized using the chemical bath method

• Published in: Journal of luminescence Vol. 143; pp. 463 - 468
• Main Authors: Koao, L.F., Dejene, F.B., Swart, H.C., Botha, J.R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-11-2013; Elsevier
• Subjects: Auger electron spectroscopy; Augers; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Flower-like; Grain size; Growth from solid phases (including multiphase diffusion and recrystallization); Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Low concentrations; Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Morphology; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Physics; Scanning electron microscopy; Spectra; Zinc oxide; ZnO; ZnO:Ce doped; ZnO; Auger electron spectroscopy; ZnO:Ce doped; Flower-like; Grain size; Scanning electron microscopy; Powders; Chemical bath deposition; Surface morphology; Crystallization; Doping; Luminescence; Cerium; Doped materials; Binary compounds; Zinc Oxides; XRD; Reflectivity; Hexagonal lattices; Optical properties; Cerium additions; Zinc oxide; Microstructure
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2013.05.045

Ce3+ doped ZnO flower-like structures were synthesized by the chemical bath deposition method (CBD). The influence of Ce3+ as a dopant on the crystallization, surface morphology, optical and luminescent properties of ZnO flowers-like structures were investigated. The X-ray diffraction (XRD) spectra of the ZnO:Ce3+nanostructures correspond to the various planes of a single hexagonal ZnO phase for the lower Ce concentration samples. The estimated grain sizes calculated using the XRD spectra were found to be in order of 42±2nm. The grain size was found to be not dependent on the concentration of the Ce3+ ions used up to 3mol% of Ce. Scanning Auger electron microscopy and scanning electron micrographs indicate that the addition of Ce3+ influence the morphology of the samples. The flower-like structures obtained for the undoped and low concentration Ce doped ZnO changed into a mixed structure with the emergence of pyramid shapes for higher concentration Ce doped samples. The solid undoped and low concentration Ce doped powder showed good optical properties with a high reflectance in the visible regions. The properties, however, diminished at higher Ce concentration. The band gap energies decreased linearly with concentration from 3.0±0.1 to 2.4±0.3eV for ZnO:0mol% Ce3+ up to ZnO:10mol% Ce3+. Under 248nm excitation, the undoped and low concentration Ce doped ZnO flower-like rods exhibited a green emission, peaking at about 559nm. The higher Ce concentration (0.3mol% and above) was emitted at 436 and 503nm due to the Ce transitions. The intensity of these emission spectra of the ZnO:Ce3+ decreased with the addition of more Ce3+ ions.
•Ce3+ doped ZnO flower-like structures were synthesized by CBD.•Flower-like hexagonal ZnO:Ce3+nanostructures were obtained for undoped and low mol% Ce.•ZnO changed into a mixed structure with emergence of pyramid shapes for higher mol% Ce.•Good optical properties with a high reflectance in the visible region were obtained.•The band gap energies decreased linearly with Ce concentration.