A novel exposed facet dependent topological transformation mechanism from hydrozincite microspheres into hierarchical mesoporous ZnO structures

作者：Li, Haitao; Zhao, Kun; Tian, Shouqin; Zeng, Dawen^*; Pang, Aimin; Wang, Xiaoxia; Xie, Changsheng

来源：Materials Letters, 2017, 202: 142-145.

DOI：10.1016/j.matlet.2017.05.030

• Nanocrystalline materials
• Crystal structure
• ZnO
• Topological transformation
• Exposed facets
• Hydrozincite

Distinct from normal hierarchical mesoporous ZnO structures exposed with (2 1 10) facets derived from polycrystal hydrozincite precursors exposed with (010) facets, single-crystal hydrozincite precursors with exposed (001) facets were prepared by a hydrothermal method assisted with sodium citrate and then topologically transformed into hierarchical mesoporous ZnO microspheres with exposed (0001) facets by calcination. To reveal the transformation process, a novel exposed facet dependent topological transformation mechanism was proposed as follows. Firstly, C-O bonds and -OH bonds in Zn-5(CO3)(2)(OH)(6) were broken with H2O and CO2 gases releasing; secondly, the remaining Zn atoms and O atoms rearranged their positions, leading to a transformation from a unit cell of monoclinic hydrozincite into eight unit cells of wurtzite ZnO based on their relationship of crystal lattice parameter. As a result, the (010) and (001) facets of hydrozincite can be transferred into the (2 -1 -10) and (0001) facets of wurtzite ZnO, respectively. In this sense, the exposed facets of hydrozincite precursors determined the exposed facets of ZnO micro/nano structures. Therefore, the transformation mechanism can be also used to synthesize other metal oxide structures with special exposed facets.

• 出版日期2017-9-1
• 单位硅酸盐建筑材料国家重点实验室; 湖北文理学院; 华中科技大学; 武汉理工大学; 湖北大学