Abstract ZnO nanorods (NRs) and ZnWO4/ZnO heterostructure, using TiO2 seed layers, were synthesized by two steps hydrothermal method and annealed at 450 °C for 2 hr. The results showed that the ZnWO4 was grown on the hexagonal ZnO NRs and change to hierarchically structure when the citric acid content was increased. All samples were applied as photoanode for photoelectrochemical (PEC) water splitting cell. As the result, the 50ZnW/ZnO sample showed the best performance of the PEC water splitting process than others. From the Electrochemical Impedance Spectroscopy (EIS) study, the Nyquist plot of 25ZnW/ZnO and 50ZnW/ZnO samples showed smaller arc compared to ZnO NRs. This is signified that the ZnWO4/ZnO heterostructure has greater charge transfer between the photoanode and electrolyte than the pristine ZnO. Hence, the modified ZnWO4 on the ZnO surface enhances the performance of ZnO NRs based PEC water splitting cell for the UV light hydrogen fuel generation.

中文翻译：

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柠檬酸对合成用于光电化学分解水的 ZnWO4/ZnO 纳米棒的影响

摘要 ZnO 纳米棒 (NRs) 和 ZnWO4/ZnO 异质结构，使用 TiO2 种子层，通过两步水热法合成，并在 450 °C 下退火 2 小时。结果表明，随着柠檬酸含量的增加，ZnWO4 生长在六方 ZnO NRs 上并转变为分级结构。所有样品均用作光电化学（PEC）水分解电池的光电阳极。结果，50ZnW/ZnO 样品比其他样品显示出 PEC 水分解过程的最佳性能。根据电化学阻抗谱 (EIS) 研究，与 ZnO NR 相比，25ZnW/ZnO 和 50ZnW/ZnO 样品的 Nyquist 图显示出更小的电弧。这表明 ZnWO4/ZnO 异质结构在光阳极和电解质之间比原始 ZnO 具有更大的电荷转移。因此，