Qu Jiangshan, Wang Yueshuai, Mu Xulin, Hu Jingcong, Zeng Bin, Lu Yue, Sui Manling, Li Rengui, Li Can
State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, P. R. China.
University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Adv Mater. 2022 Sep;34(37):e2203320. doi: 10.1002/adma.202203320. Epub 2022 Aug 15.
Titanium dioxide (TiO ) nanocrystals have attracted great attention in heterogeneous photocatalysis and photoelectricity fields for decades. However, contradicting conclusions on the crystallographic orientation and exposed facets of TiO nanocrystals frequently appear in the literature. Herein, using anatase TiO nanocrystals with highly exposed {001} facets as a model, the misleading conclusions that exist on anatase nanocrystals are clarified. Although TiO -001 nanocrystals are recognized to be dominated by {001} facets, in fact, anatase nanocrystals with both dominant {001} and {111} facets always co-exist due to the similarities in the lattice fringes and intersection angles between the two types of facets (0.38 nm and 90° in the [001] direction, 0.35 nm and 82° in the [111] direction). A paradigm for determining the crystallographic orientation and exposed facets based on transmission electron microscopy (TEM) analysis, which provides a universal methodology to nanomaterials for determining the orientation and exposed facets, is also given.
几十年来，二氧化钛（TiO₂）纳米晶体在多相光催化和光电领域备受关注。然而，关于TiO₂纳米晶体的晶体取向和暴露晶面的相互矛盾的结论在文献中经常出现。在此，以具有高度暴露{001}晶面的锐钛矿型TiO₂纳米晶体为模型，澄清了关于锐钛矿型纳米晶体存在的误导性结论。尽管TiO₂-001纳米晶体被认为以{001}晶面为主，但实际上，由于两种晶面（[001]方向上为0.38 nm和90°，[111]方向上为0.35 nm和82°）的晶格条纹和交角相似，具有主导{001}和{111}晶面的锐钛矿型纳米晶体总是共存的。还给出了一种基于透射电子显微镜（TEM）分析确定晶体取向和暴露晶面的范例，该范例为纳米材料确定取向和暴露晶面提供了一种通用方法。
