Improving the hydrophilic and antifouling properties of polyvinylidene fluoride membrane by incorporation of novel nanohybrid GO@SiO2 particles

Novel high-flux and antifouling membranes were prepared by introducing the three-dimensional structure nanohybrid particle (GO@SiO2) and polyvinylpyrrolidone (PVP) into polyvinylidene fluoride (PVDF) casting solution. GO@SiO2 nanohybrid particle was produced via in situ hydrolysis and condensation of precursor tetraethoxysilane (TEOS) on the surfaces of graphene oxide (GO) nanosheets, and the nanohybrid membranes were first prepared through phase inversion by an immersion precipitation technique. Compared with PVDF/PVP, PVDF/SiO2/PVP and PVDF/GO/PVP membranes, PVDF/GO@SiO2/PVP membrane had outstanding performance in hydrophilicity, surface roughness, and mechanical force. The rejection rate of bovine serum albumin (BSA) exceeded 78.5% under high water flux (1232 L/(m(2) h)) and the membrane flux recovery rate was highest (BSA = 77.5%, sodium alginate (SA) = 82.1%). To investigate the antifouling properties of the nanohybrid membrane further, the adhesion forces of foulant and membrane were determined using our own foulant probes with an atomic force microscope (AFM). The results showed that the adhesion forces between PVDF/GO@SiO2/PVP membrane and foulants (BSA and SA) were far smaller than the adhesive forces of the foulants with the PVDF/PVP membrane. The results showed that the new nanohybrid membrane had the best overall properties and antifouling ability, and it provides a new method for improving the performance of PVDF membranes. (C) 2016 Elsevier B.V. All rights reserved.