Co Doped ZnO Nanowires as Visible Light Photocatalysts

Solid State Sciences 2016
Andris Šutka, Tanel Käämbre, Rainer Pärna, Inna Juhņeviča, Mihael Maiorov, Urmas Joost, Vambola Kisand

High aspect ratio cobalt doped ZnO nanowires showing strong photocatalytic activity and moderate ferromagnetic behaviour were successfully synthesized using a solvothermal method and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), vibrating sample magnetometry (VSM) and UVevisible absorption spectroscopy. The photocatalytic activities evaluated for visible light driven degradation of an aqueous methylene orange (MO) solution were higher than for Co doped ZnO nanoparticles at the same doping level and synthesized by the same synthesis route. The rate constant for MO visible light photocatalytic degradation was 1.9$10
3 min
1 in case of nanoparticles and 4.2$10
3 min
1 in case of nanowires. We observe strongly enhanced visible light photocatalytic activity for moderate Co doping levels, with an optimum at a composition of Zn0.95Co0.05O. The enhanced photocatalytic activities of Co doped ZnO nanowires were attributed to the combined effects of enhanced visible light absorption at the Co sites in ZnO nanowires, and improved separation efficiency of photogenerated charge carriers at optimal Co doping.

Keywords
Zinc oxide, Doping, Nanowires, Photocatalyst, Chemical synthesis, Photoelectron spectroscopy
DOI
10.1016/j.solidstatesciences.2016.04.008
Hyperlink
http://www.sciencedirect.com/science/article/pii/S1293255816301947

Šutka, A., Käämbre, T., Pärna, R., Juhņeviča, I., Maiorov, M., Joost, U., Kisand, V. Co Doped ZnO Nanowires as Visible Light Photocatalysts. Solid State Sciences, 2016, Vol.56, pp.54-62. ISSN 1293-2558. Available from: doi:10.1016/j.solidstatesciences.2016.04.008

Publication language
English (en)