Enhanced Photocatalytic Activity of Mg-Doped ZnO Nanorods Prepared by Electrodeposition

Mg-doped ZnO nanorods were prepared by electrochemical deposition method in aqueous solution. To test the sample, the results show that the sample presents a rod-like shape with hexagonal cross sections and typical morphology of wurtzite ZnO, and (002) diffraction peak of Mg-doped ZnO nanorods move to large-angle direction in XRD. The peak of Mg element has appeared in EDS. XPS shows that there is Mg-O binding in the sample. PL spectrums of the samples are observed at room temperature, the UV emission of Mg-doped ZnO presents blue shift compared with undoped ZnO, absorption spectrum shows that band gap of Mg-doped ZnO is larger. We can reach the conclusion that the Zn2+ ions are successfully substituted by Mg2+ ions in the ZnO lattice. In addition, photocatalysis property of Mg-doped ZnO nanorods is investigated. It is found that the degradation efficiency of methyl orange raise twice by Mg-doped ZnO nanorods in comparison to undoped ZnO nanorods. The result indicates that the photocatalysis activity of ZnO nanorods can enhance after Mg2+ ions are doped into ZnO lattice.