Preparation of Zn x V y O/ZnO heterojunction for enhanced photocatalytic activity

Solar energy utilization is regarded as one of the most promising and cost-effective approaches to solve energy and environmental problems. In the present work, a series of V-doped ZnO films with different V contents are produced by co-sputtering deposition for the photocatalytic applications. It is found that the introduction of V elements has a significant effect on the morphology, band structure and photoelectric properties of the material. The photocurrent response of Zn x V y O (V∼15%) sample enriches a value of 0.47 mA/cm 2 at a constant voltage of 1.23 V (vs. RHE), which is about 2.2 times higher than that of undoped ZnO. In addition, the n-n heterojunctions combined with Zn x V y O and ZnO are prepared. Compared with Zn x V y O (V∼15%) sample, the photocurrent response of Zn x V y O (V∼15%)/ZnO is further improved by about 68%, reaching 0.79 mA/cm 2. It is confirmed that the Zn x V y O (V∼15%)/ZnO heterojunctions structure could effectively inhibit the recombination of carriers and enhance the oxidation reaction.