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Recently, the membrane separation materials show promising applications in the fields of crude oil removal because of their low energy consumption and less secondary pollution. However, the membrane separation materials suffer problem of low separation efficiency due to the high viscosity of crude oil. Here, a superhydrophobic material with Joule heat and photothermal effect was prepared by decorating the delignified wood with reduced graphene oxide (GSH) and vinyl terminated polydimethylsiloxane (V-PDMS) through thiol-ene click reaction. The prepared PDMS@GSH wood exhibited stable superhydrophobicity with a water contact angle of 156°. Meanwhile, the GSH layer provided promising electrothermal effect that endowed the PDMS@GSH wood with excellent crude oil/water separation capability under the Joule heat with a surface temperature of 139 °C and separation rate of 1.78 × 105 kg m−3 h−1. Besides, the PDMS@GSH wood displayed a good photothermal effect that assisted with the Joule heat to heat the wood for crude oil removal to save energy. More importantly, the PDMS was crosslinked with GSH on the wood via thiol-ene click reaction, leading to the stable superhydrophobicity and electrical conductivity in strong acid or alkali environment. This material has broad application prospects in crude oil clean-up due to its high separation speed and easy large-scale production. [Display omitted] • A new strategy for fabricating superhydrophobic wood with heating property is proposed. • The wood presents stable superhydrophobicity and electrical conductivity. • The wood shows excellent Joule heat and photothermal effect. • The wood exhibits high separation rate for viscous crude oil wastewater. [ABSTRACT FROM AUTHOR]

Superhydrophilic/underwater superoleophobic coatings that effectively prevent viscous oil contamination have been of considerable interest for the great potential in oil spill remediation and oilfield wastewater treatment. In the present work, a protonated cross-linkable nanocomposite coating with robust underwater superoleophobicity and intensified hydration capability is proposed through the synthesis of active polymeric nanocomplex (PNC), cross-linking reaction between PNC and hydrophilic chitosan (CS), and final protonation to further improve water affinity. Benefiting from the hierarchical structure and strong hydration capability induced by electrostatic interactions and hydrogen bondings, the nanocomposite coating coated textile exhibits excellent superhydrophilicity (within 0.28 s with water contact angle reaching 0°), underwater superoleophobicity (underwater crude oil contact angle at 160°), and ultralow oil adhesion even to highly viscous silicone oil. Moreover, the nanocomposite coating presents a robust chemical resistance, mechanical tolerance, and storage stability. Simultaneously, the nanocomposite coating adapts well to various porous substrates (e.g., stainless steel mesh and Ni sponge) with great anti-oil-fouling and self-cleaning performances. Importantly, the coating coated textile is successfully applied in crude oil/water separation with excellent efficiency and repeatability. The findings conceivably stand out as a new methodology to fabricate superhydrophilic/underwater superoleophobic materials with outstanding anti-viscous oil-fouling property for practically treating oily wastewater. [Display omitted] • A protonated cross-linkable nanocomposite coating with underwater superoleophobicity is reported. • The PPNC-CS coating presents an outstanding hydration capability induced by charges. • The PPNC-CS coating exhibits ultralow oil adhesion even to viscous silicone oil. • The PPNC-CS adapts well to various porous substrates with great anti-oil-fouling performance. • The PPNC-CS coated textile is successfully applied in crude oil/water separation. [ABSTRACT FROM AUTHOR]

Recently, the crude oil spill has brought inevitable harm to the global ecological environment. Due to the high-viscosity crude oil, it is wise to take advantage of the photothermal/electrothermal effects of the membrane to separate the crude oil from the water. However, the functional separation membrane always suffers from low photothermal/electrothermal effects and poor stability. Herein, the vinyl polyvinylidene fluoride/mercapto carbon nanotubes@vinyl-terminated polydimethylsiloxane (PVDF-a/CNT-s@PDMS) membrane with fast photothermal/electrothermal effects and organic absorption property was successfully prepared by electrospinning and multi-layer loading method. The prepared PVDF-a/CNT-s@PDMS membrane resisted a variety of liquids and had stable superhydrophobicity (WCA = 156°). Furthermore, the membrane maintained superhydrophobicity even suffer from water and milk under the applied voltage condition. After 100 wear resistance tests, the membrane maintained stable superhydrophobicity and the separation rate remained unchanged. The surface temperature of the membrane rapidly approached to the maximum temperature in 30 s, showing a rapid photothermal/electrothermal effects, and the average separation rate of crude oil was 1185 kg m−2 h−1·bar−1. Meanwhile, the membrane exhibited outstanding efficiency for separate immiscible oil-water mixtures. Importantly, the incorporation of the sulfhydryl group enhanced the special ability of the composite membrane to adsorb organic dyes from oil phase. Therefore, the PVDF-a/CNT-s@PDMS membrane has a wide range of potential application in the domain of oil-water separation. [Display omitted] • The superhydrophobic membrane exhibited high stability toward abrasion. • The obtained membrane possessed fast photothermal/electrothermal response. • The membrane effectively achieved various oil/water mixture separation. • The membrane possessed ability for the adsorption of organic dyes from the oil phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully organic and biodegradable superhydrophobic sponge is rationally constructed. • All of raw materials are derived from cheap renewable natural resources. • The sponge presents great separation performance for immiscible oil/water mixtures. • Multi-layer compressed porous structure achieves gravity-driven high-flux emulsion separation. Facile fabrication of functional superhydrophobic porous materials with full biodegradability for efficient removal of oily pollutants from water has been of considerable interest for its great significance in environmental protection. Herein, a fully organic and biodegradable superhydrophobic sponge is fabricated with carnauba wax (CW) via dip-coating, nonsolvent induced phase separation and spraying processes on a freeze-dried pomelo peel. The as-fabricated sponge was covered with flower-shaped patterns aggregated by CW nanosheets, and presented great water repellency with a contact angle of 154°. Thanks to the 3D porous architecture and superhydrophobicity/superoleophilicity, the sponge exhibited great oil absorptive capacity, oil selectivity, separation efficiency and reusability for immiscible oil/water mixtures. Interestingly, the multi-layer compressed sponges realized gravity-driven surfactant-stabilized water-in-oil emulsion separation with high permeation flux of up to 5729 L·m−2·h−1 and excellent efficiency of oil purity larger than 99.9%. Importantly, the superhydrophobic sponge was derived from cheap renewable natural resources, and capable of being completely biodegraded after discarding. The findings conceivably stand out as a new tool to fabricate superhydrophobic materials with sustainability and biodegradability for oil accidents and industrial sewage emissions. [ABSTRACT FROM AUTHOR]