Oriented attachment: a versatile approach for construction of nanomaterials

In this paper, we review the recent development of synthetic architecture of nanomaterials through oriented aggregations of primary colloidal particles. Various organising manners via this mechanism have been illustrated, and the relationships among zero-, one-, two-, and three-dimensional (0D, 1D, 2D and 3D) materials in the structural transformations have been elucidated systematically. In addition to straight linear attachments, nanobuilding blocks can also arrange themselves into curvatures, generating ring-like nanostructures (i.e., 2D hollow structures). Furthermore, three-dimensional structures with an interior space (i.e., 3D hollow structures) have been prepared through the same mechanism, including symmetric and asymmetric geometrical structures. On the basis of these works, it has been proven that the oriented attachment is a versatile approach for the design and synthesis of nanomaterials; it can be involved entirely or only partially in the material construction, and further coupling with chemical reactions and/or physical processes is still possible. Future directions in this research field have also been addressed.