Ultralight and multifunctional PVDF/SiO2@GO nanofibrous aerogel for efficient harsh environmental oil-water separation and crude oil absorption

Abstract

The accumulative disasters about oil spills and industrial emissions create increasingly environmental problems, and high-performance absorbent materials have attracted wide attention to providing available solution. Herein, polyvinylidene fluoride/SiO2@graphene oxide (PVDF/SiO2@GO) aerogels were prepared by cross-linking of the electrospun PVDF/SiO2 nanofibers and GO skeleton. By changing the content of SiO2 nanoparticles in the PVDF nanofibers, the porosity and surface roughness of the composite aerogels could be controlled. Compared with PVDF@GO aerogel, the PVDF/SiO2@GO (PSG) aerogels had higher mechanical properties and hydrophobicity. And, the PSG-2 aerogel (1 wt% SiO2 contained in nanofibers) exhibited stable structure, excellent oil absorption capacity (129–264 g g−1), great flame retardancy and reusability. After being pretreated with strong acid and alkali, it remained strong hydrophobicity, indicating it possessed excellent chemical resistance. More importantly, it could also separate oil-water mixture by gravity under harsh environment (strong acid/alkali), which exhibited excellent separation performance with flux of 42402 L m−2 h−1 (chloroform/water mixture) and separation efficiency of 99.96%. Moreover, it could clean up viscous crude oil rapidly by photothermal effect, and the crude oil absorption time of heated PSG-2 was reduced by 99.65%. The PSG aerogels provide a new choice for efficient and continuous harsh environmental oil-water separation and crude oil absorption.