Intercalating petroleum asphalt into electrospun ZnO/Carbon nanofibers as enhanced free-standing anode for lithium-ion batteries

Abstract

In this study, we demonstrate novel 3D interconnected nanofiber films by intercalating petroleum asphalt into electrospun ZnO/carbon nanofibers (ZnO/CNFs-PA) as enhanced free-standing anode for lithium-ion batteries (LIBs). ZnO/CNFs composite is synthesized via one-step electrospinning of polyacrylonitrile and zinc acetate dehydrate. Through solvent impregnation and subsequent two-step thermal treatments, appropriate amount of petroleum asphalt (PA) is intercalated into ZnO/CNFs to generate a conductive carbon film between and around the nanofibers. Benefitting from the 3D conductive network established by the carbon nanofibers and PA-carbon layer, the as-prepared ZnO/CNFs-PA-1.0 film is evaluated as a free-standing LIBs anode and exhibits a promoted reversible capacity of 702 mA h g−1 at current density of 200 mA g−1, associating with excellent cycling stability and rate performance. Such novel nanostructure can effectively accommodate the volume expansion of ZnO, facilitate charge transfer and reinforce the electrode. The present strategy is believed to provide a feasible method to produce transition metal oxide/carbon nanofibers electrodes with superior electrochemical performance for LIBs.