title: Optical properties of sol-gel synthesized calcium doped ZnO nanostructures.
abstract: Optical properties of Ca doped ZnO nanoparticles prepared at room temperature through wet chemical method have been investigated. X-ray diffraction studies show that particles are crystalline in nature and doping did not induce impurity phases. Optical absorption measurements show an absorption peak at ∼372 nm which is due to excitonic absorption of the ZnO. Photoluminescence studies reveal a broad emission at an excitation wavelength of 335 nm and the bands are attributed to near band edge emission, oxygen vacancies, surface dangling bonds and zinc interstitials. Incorporating Ca(2+) induces reduction in near band edge emission and there is an enhancement in the oxygen vacancy peaks which are attributed to the shape changes in the nanoparticles.
authors.affiliation: Department of Physics, National Institute of Technology, Tiruchirappalli 620 015, India. balkarin@yahoo.com
authors.forename: B
authors.initials: B
authors.lastname: Karthikeyan
authors.forename: T
authors.initials: T
authors.lastname: Pandiyarajan
authors.forename: K
authors.initials: K
authors.lastname: Mangaiyarkarasi
mesh_terms: D002118:Calcium / Q000737:chemistry*; D002621:Chemistry / Q000379:methods*; D004563:Electrochemistry / Q000379:methods; D008027:Light; D049449:Luminescence; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D044367:Phase Transition; D010777:Photochemistry / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D014961:X-Ray Diffraction / Q000379:methods; D014965:X-Rays; D015032:Zinc / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D015032:Zinc; D015034:Zinc Oxide; D002118:Calcium