title: Electrospun Superhydrophobic Organic/Inorganic Composite Nanofibrous Membranes for Membrane Distillation.
abstract: Electrospun superhydrophobic organic/inorganic composite nanofibrous membranes exhibiting excellent direct contact membrane distillation (DCMD) performance were fabricated by a facile route combining the hydrophobization of silica nanoparticles (SiO2 NPs) and colloid electrospinning of the hydrophobic silica/poly(vinylidene fluoride) (PVDF) matrix. Benefiting from the utilization of SiO2 NPs with three different particle sizes, the electrospun nanofibrous membranes (ENMs) were endowed with three different delicate nanofiber morphologies and fiber diameter distribution, high porosity, and superhydrophobic property, which resulted in excellent waterproofing and breathability. Significantly, structural attributes analyses have indicated the major contributing role of fiber diameter distribution on determining the augment of permeate vapor flux through regulating mean flow pore size (MFP). Meanwhile, the extremely high liquid entry pressure of water (LEPw, 2.40 ± 0.10 bar), robust nanofiber morphology of PVDF immobilized SiO2 NPs, remarkable mechanical properties, thermal stability, and corrosion resistance endowed the as-prepared membranes with prominent desalination capability and stability for long-term MD process. The resultant choreographed PVDF/silica ENMs with optimized MFP presented an outstanding permeate vapor flux of 41.1 kg/(m(2)·h) and stable low permeate conductivity (∼2.45 μs/cm) (3.5 wt % NaCl salt feed; ΔT = 40 °C) over a DCMD test period of 24 h without membrane pores wetting detected. This result was better than those of typical commercial PVDF membranes and PVDF and modified PVDF ENMs reported so far, suggesting them as promising alternatives for MD applications.
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Xufeng
authors.initials: X
authors.lastname: Yu
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Cheng
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Deng
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: State Key Lab for Modification of Chemical Fibers and Polymer Materials, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Xuefen
authors.initials: X
authors.lastname: Wang
keywords: colloid electrospinning; membrane distillation; nanofibrous membrane; silica nanoparticles; superhydrophobicity