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Zinc oxide thin films have been grown by electrodeposition technique onto Cu and ITO-coated glass substrates from an aqueous zinc nitrate solution with addition of sodium thiosulfate at 90 ℃.The effects of sodium thiosulfate on the electrochemical deposition of ZnO were investigated by cyclic voltammetry and chronoamperometry techniques.Deposited films were obtained at-0.60 V vs.SCE and characterized by XRD,SEM,FTIR,optical,photoelectrochemical and electrical measurements.Thickness of the deposited film was measured to be357 nm.X-ray diffraction results indicated that the synthesized ZnO has a pure hexagonal wurtzite structure with a marked preferential orientation along(002) plane.FTIR results confirmed the presence of ZnO films at peak558 cm~(-1).SEM images showed uniform,compact morphology without any cracks and films composed of large flower-like ZnO agglomerates with star-shape.Optical properties of ZnO reveal a high optical transmission(>80%)and high absorption coefficient(α > 10~5 cm~(-1)) in visible region.The optical energy band gap was found to be 3.28 eV.Photoelectrochemical measurements indicated that the ZnO films had n-type semiconductor conduction.Electrical properties of ZnO films showed a low electrical resistivity of 6.54 Ω·cm,carrier concentration of-1.3× 10~(17)cm~(-3) and mobility of 7.35 cm~2V~(-1)s~(-1).
Zinc oxide thin films have been grown by electrodeposition technique onto Cu and ITO-coated glass substrates from an aqueous zinc nitrate solution with addition of sodium thiosulfate at 90 ° C. The effects of sodium thiosulfate on the electrochemical deposition of ZnO were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were obtained at-0.60 V vs. SEC and characterized by XRD, SEM, FTIR, optical, photoelectrochemical and electrical measurements. Thinness of the deposited film was measured to be 357 nm. X- ray diffraction results indicating that ZnO has a pure hexagonal wurtzite structure with a marked preferential orientation along (002) plane. FTIR results confirmed the presence of ZnO films at peak 558 cm -1. SEM images showed uniform, compact morphology without any cracks and films composed of large flower-like ZnO agglomerates with star-shape. Optical properties of ZnO reveal a high optical transmission (> 80%) and high absorption coefficient (a> 10 ~ 5 cm -1) in visible region. The optical energy band gap was found to be 3.28 eV. Photoelectrochemical measurements indicated that the ZnO films had n-type semiconductor conduction. Electrical properties of ZnO films showed a low electrical resistivity of 6.54 Ω · cm, carrier concentration of-1.3 × 10 ~ (17) cm -3 and mobility of 7.35 cm ~ 2V -1 s -1.