Electrospun TiO_2-Based Photocatalysts

摘要

Solar-driven semiconductor photocatalysis shows great potential to solve growing energy and environmental crises. Electrospun TiO_2 nanofibers (NFs) attract attention due to their chemical stability, nontoxicity, cheapness, large specific surface area, and porous structures. The unique unwoven nanofibrous network facilitates mass transportation compared with bulk materials. Electrospun TiO_2 NFs are an ideal substrate for growing secondary nanostructures and constructing heterojunction photocatalysts. The hybrid heterojunctions show enhanced electron-hole separation, improved light absorption, effective activation of reactants, and therefore increased photocatalytic performance. Herein, the electrospinning principle and preparing tactics of electrospun TiO_2 fibrous nanostructures including solid, hollow, and core/shell NFs are first described. The construction strategies of electrospun TiO_2-based heterojunctions by loading electron or hole cocatalysts and hybridizing secondary semiconductors to engineer catalytic active sites and steer charge carrier separation are outlined. Dopant-induced increased light absorption and enhanced charge transfer of TiO_2 NFs are discussed. Further, the applications of electrospun TiO_2-based photocatalysts for solar-to-chemical conversion and environmental remediation are elucidated. Finally, the challenges and perspectives for the development of electrospun TiO_2-based photocatalysts are underlined, which deepen a systematic understanding of the design and fabrication of more efficient electrospun NFs in the future.