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Carbon nanofibrous nonwoven mats (CNFMs) prepared via electrospinning offer excellent electrical and structural properties and have been used as frameworks for electrodes in electrochemical energy storage devices. However, lack of mechanical strength hinders the broad applications of CNFMs in flexible electronics or industry use. In this work, a rapid stabilization method is developed to prepare high-strength and flexible CNFMs. Studies of the effects of stabilization time on the structures of the stabilized polyacrylonitrile (PAN) nanofibers and the subsequent carbon nanofibers reveal that there is an optimal stabilization time for making high-strength CNFMs. Long stabilization time results in excessive oxidation of the stabilized PAN nanofibers and unwanted defects in the carbon nanofibers. Short stabilization time results in carbon nanofibers with less crystalline structures due to insufficient formation of the thermally stable ladder-like structure. Robust and flexible CNFM with the highest tensile strength of 192.7 MPa is obtained using an optimized total stabilization time of 40 min. To demonstrate the application of the flexible CNFMs, they are fabricated as an electrode framework to load TiO2 nanoparticles without use of organic binders. Lithium ion half-cell based on this electrode demonstrates superior rate cycling performance owning to the porous structure and highly conductive fibrous carbon network of CNFM. [ABSTRACT FROM AUTHOR]

Carbon nanofibers with diameters that fall into submicron and nanometer range have attracted growing attention in recent years due to their superior chemical, electrical, and mechanical properties in combination with their unique 1D nanostructures. Unlike catalytic synthesis, electrospinning polyacrylonitrile (PAN) followed by stabilization and carbonization has become a straightforward and convenient route to make continuous carbon nanofibers. This paper is a comprehensive and state-of-the-art review of the latest advances made in development and application of electrospun PAN-based carbon nanofibers. Our goal is to demonstrate an objective and overall picture of current research work on both functional carbon nanofibers and high-strength carbon nanofibers from the viewpoint of a materials scientist. Strategies to make a variety of carbon nanofibrous materials for energy conversion and storage, catalysis, sensor, adsorption/separation, and biomedical applications as well as attempts to achieve high-strength carbon nanofibers are addressed. [ABSTRACT FROM AUTHOR]