Development of low-cost electrospun carbon nanofibers using asphaltene precursor

Abstract

This study reports for the first time the development of low-cost nano-scale carbon fibers from petroleum asphaltene precursors using the simple and cost-effective electrospinning technique. Firstly, the green nanofiber nonwoven mats were electrospun without any prior treatment of the asphaltene feedstock. The nanomats were then heat treated at different temperatures to optimise their thermostabilisation and carbonisation conditions. Based on extensive mechanical and analytical (DSC, TGA, ATR-FTIR) characterisations, it was found that thermostabilisation of fibers at 250 °C in air followed by carbonisation at 1000 °C in nitrogen resulted in nanofibers with the best tensile properties (∼340 MPa) and good morphology as also confirmed by SEM micrographs. Moreover, the nanofiber mats exhibited relatively good electrical conductivity (5.88 ± 0.43 S cm−1), which could be useful for energy storage applications. The average diameter of the carbonised nanofibers was found to be 700 nm, and the carbonised nanofiber mats were flexible and showed good handleability despite the inherent brittleness of asphaltenes. Overall, the present work opens new avenues for the valorisation of asphaltene waste into high-value nanofiber materials with the potential for multi-functional applications in the composite and energy industries.