In this article, we review our recent research efforts on the synthesis, crystallinity control, and photocatalysis of nanostructured titanium dioxide (TiO2) shells. First, we introduce several synthetic methods for preparing TiO2 shell structures using either template-free or template-assisted approaches. Several methods to change the structures from amorphous to crystalline and subsequently ways to enhance the crystallinity are then discussed, including those involving the “silica-protected calcination” and “partial etching and recalcination” strategies. We also discuss the photocatalytic applications of the TiO2 nanoshells and the methods for improving their catalytic activities. Finally, we conclude with a summary and our perspective on the further development of the nanostructured TiO2 shells. It is believed that more rational design and modification strategies such as well-controlled nonmetal doping, plasmonic metal decoration and the hybridization with other semiconducting materials will significantly enhance the photocatalytic efficiency of TiO2-based catalyst materials.
