title: Photoconductivity and photoluminescence of ZnO nanoparticles synthesized via co-precipitation method.
abstract: Photoconductivity and photoluminescence studies of ZnO nanoparticles (NPs) synthesized by co-precipitation method capped with thioglycerol are carried out. The effect of annealing at 300°C is also studied. The transmission electron micrograph (TEM) and X-ray diffraction (XRD) pattern confirm the hexagonal wurtzite structure of ZnO nanoparticles. The UV-vis absorption spectrum of ZnO NPs shows blue shift of absorption peak as compared to bulk ZnO. The photoluminescence (PL) spectra of as-synthesized ZnO NPs show band edge emission as well as blue-green emission. After annealing band edge emission is quenched. Photocurrent is found to vary super linearly at high voltage for both as-synthesized as well as annealed ZnO NPs. Time resolved rise and decay photocurrent spectra are found to exhibit anomalous photoconductivity for as-synthesized as well as annealed ZnO NPs wherein the photocurrent decreases even during steady illumination.
authors.affiliation: Department of Physics, University of Allahabad, Allahabad 211002, India. ram_kripal2001@rediffmail.com
authors.forename: Ram
authors.initials: R
authors.lastname: Kripal
authors.forename: Atul K
authors.initials: AK
authors.lastname: Gupta
authors.forename: Rajneesh K
authors.initials: RK
authors.lastname: Srivastava
authors.forename: Sheo K
authors.initials: SK
authors.lastname: Mishra
mesh_terms: D008027:Light; D049449:Luminescence; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry*; D010777:Photochemistry; D013056:Spectrophotometry, Ultraviolet; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D015034:Zinc Oxide