Electrospun carbon nanodot-doped PVDF nanofibers with enhanced crystallinity, hydrophobicity and UV resistance

Abstract

PVDF is known to be synthesized into nanofibers for various applications, including wastewater treatment through oil–water separation, adsorption, and filtration. However, long-term stability and fouling remain significant shortcomings. In this study, low-cost, steam-activated date palm fronds carbon nanodots (DPF CNDs) derived from natural sources were incorporated into polyvinylidene fluoride (PVDF) nanofiber mats at varying concentrations ranging from 0 to 5 wt%. We investigated the impact of CNDs loading on surface morphology, wettability, crystalline structure, thermal stability, mechanical properties, and UV resistance. We found that α-phase crystallinity increased with increasing CND concentration; the membranes also exhibited thermal stability, with a slightly decreasing melting temperature. Additionally, a slight decrease in tensile strength was observed with increasing elongation at break, as measured by mechanical testing, indicating improved flexibility. Enhanced hydrophobicity was also observed, as evidenced by a higher contact angle that remained stable after UV exposure, thereby demonstrating improved UV resistance. Therefore, these CND-doped PVDF nanofibers demonstrated potential for antifouling applications, particularly in the adsorption of organic pollutants and oil–water separation.