A superhydrophobic poly(lactic acid) electrospun nanofibrous membrane surface-functionalized with TiO2 nanoparticles and methyltrichlorosilane for oil/water separation and dye adsorption

Abstract

A functionalized nanofiber membrane with high oil/water separation efficiency and methylene blue adsorption has been successfully fabricated by electrospinning and a surface modification approach. The substrate poly(lactic acid) (PLA) nanofiber film was firstly coated with titanium dioxide (TiO₂) nanoparticles (NPs) by the sol–gel method. Then, polysiloxane formed by the hydrolysis and polycondensation of methyltrichlorosilane (MTS) was deposited on the modified nanofiber surface to increase the surface roughness and reduce the surface energy. The PLA nanofibrous membrane functionalized with TiO₂ NPs and MTS exhibited excellent superhydrophobicity (water contact angle = 157.4 ± 0.9°), high permeation flux (2297.6 ± 51.6 L m⁻² h⁻¹) and ideal filtration efficiency (98.4 ± 1.0%). Moreover, the functionalized nanofibrous membrane could also achieve rapid and recyclable adsorption of toxic dyes such as methylene blue in aqueous solution. It provides a new prospect to facilely fabricate nanofibrous membrane materials to achieve the dual functions of oil/water separation and removal of toxic dyes with high efficiency.