Abstract In this work, hierarchical hollow ZnO microspheres with an average diameter of 3.5 μm are successfully synthesized via a simple template-free solvothermal route. And these microspheres are constructed by anisotropic single-crystalline ZnO nanorods which grows along the [0001] c-axis direction because of the selective adsorption of ethylene glycol. It is noted that ethylene glycol plays a crucial role in promoting the growth and aggregation of nanorod by comparing the effect of other solvents, such as water, ethanol, isopropanol and glycerol. Furthermore, the photocatalytic activity of as-obtained hollow ZnO microspheres is evaluated by the degradation of methylene blue (MB) in aqueous solution. The photocatalytic performance reveals that these hollow ZnO microspheres can not only efficiently degradate the dye, but also show good stability during the cycling photodegradation.

中文翻译：

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由径向排列的纳米棒组成的分级空心氧化锌微球的无模板合成和光催化活性

摘要 在这项工作中，通过简单的无模板溶剂热途径成功合成了平均直径为 3.5 μm 的分级空心 ZnO 微球。并且这些微球由各向异性单晶ZnO纳米棒构成，由于乙二醇的选择性吸附，该纳米棒沿[0001]c轴方向生长。通过比较水、乙醇、异丙醇和甘油等其他溶剂的作用，注意到乙二醇在促进纳米棒的生长和聚集方面起着至关重要的作用。此外，通过在水溶液中降解亚甲蓝 (MB) 来评估所获得的空心 ZnO 微球的光催化活性。光催化性能表明，这些空心的 ZnO 微球不仅可以有效降解染料，