Rational Fabrication of Well-Defined Mesoporous Carbon-Supported TiO2 Nanostructures for Anode Material of Lithium-Ion Batteries

Well-defined mesoporous carbon-supported TiO2 heterostructures, especially with a modulated TiO2 crystalline phase and tunable physicochemical properties of carbon support, hold great potential for numerous advanced applications, but their rational fabrication remains challenging. In this work, a kind of pyrrole-containing bifunctional block copolymer (PEO-b-PPHMA) that can serve as both a structure-directing agent for the generation of mesostructures and a precursor for the formation of robust carbon materials was synthesized to fabricate such heterostructured materials. Based on the self-assembly of PEO-b-PPHMA and its chemical transformation in confined nanochannels, a strategy for the facile construction of diverse well-defined mesoporous TiO2 with integrated carbon layer networks was developed by using a single block copolymer. Importantly, the generated carbon networks (supports) provide sufficient thermal stability to access highly crystalline TiO2 skeletons and to modulate the TiO2 crystalline phase without collapse of the preformed mesoporous structures. Moreover, not only the nitrogen content in the formed carbon layer is easily tunable by varying the treatment temperature but also the functional moieties such as plasmonic particles and redox sites can be flexibly incorporated into the formed carbon layer by employing different oxidative agents for pyrrole chemical transformation. These advantageous synthesis features enable facile and rational access to a series of well-defined mesoporous carbon-supported TiO2 heterostructures with enhanced or new properties. As a demonstration, one mesoporous carbon-supported TiO2 was prepared and used for lithium battery application, exhibiting excellent performance at the forefront of the relevant works in the literature. The obtained results indicate that our synthetic concept may offer new opportunities to develop novel TiO2 nanomaterials for diverse applications.