Electrospun Semiconductor-Based Nano-Heterostructures for Photocatalytic Energy Conversion and Environmental Remediation: Opportunities and Challenges

Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental pollution. Design and synthesis of nano-heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic processes. One-dimensional (1D) semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter, high ratio of surface to volume, small grain sizes, and high porosity, which are ideally suited for photocatalytic reactions from the viewpoint of structure advantage. After the secondary treatment of these nanofibers through the solvothermal, gas reduction, in situ doping, or assembly methods, the multi-component nanofibers with hierarchical nano-heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic processes. In recent years, the electrospun semiconductor-based nano-heterostructures have become a "hot topic" in the fields of photocatalytic energy conversion and environmental remediation. This review article summarizes the recent progress in electrospinning synthesis of various kinds of high-performance semiconductor-based nano-heterostructure photocatalysts for H-2 production, CO2 reduction, and decomposition of pollutants. The future perspectives of these materials are also discussed.