Electrospun carbon nanofibers and their hybrid composites as advanced materials for energy conversion and storage

Among the various kinds of electrospun materials, electrospun carbon nanofibers (ECNFs) represent one of the most interesting research directions in nanoscience and nanotechnology, with the capability of realizing structural and functional features through tailored designs and controlled synthesis. The degree of precision in controlling the structures, morphologies, and compositions of ECNFs, together with the incorporation of other materials, allows for the creation of nanoscale building blocks with unique electronic, catalytic, and adsorption properties, thus enabling a variety of promising opportunities in the energy-related field. This review is centered on the recent major advances in the controlled synthesis of ECNFs, and the potential of the resulting hybrid composites for energy applications. The promising energy conversion applications of ECNFs and their hybrid composites, such as in solar cells and fuel cells, are also discussed. The use of ECNFs and their hybrid composites in energy storage technologies such as batteries, supercapacitors, and hydrogen storage is then reviewed. In each case, we highlight the benefits of materials with high surface area, porous structures, and the free-standing architecture of ECNFs which act to amplify the surface activity and support other materials, leading to enhanced energy conversion and storage performance. Moreover, we provide a commentary on the challenges, as well as perspectives for potential future research on ECNFs and their hybrid materials. This review provides an overall perspective on the current state of efforts aimed at the controlled synthesis of ECNF-based materials for their various potential applications, along with the challenges remaining to be addressed, giving an insight into a promising strategy to ameliorate some of the energy issues impacting the world today.