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Passive cooling fabric that facilitates sweat‐wicking and evaporation is highly desirable for promoting human body's thermal comfort and reducing energy consumption. However, highly hydrophilic sweat‐wicking fabric fails to repel external fouling due to the contradiction between hydrophilicity and lyophobicity. Moreover, conventional passive cooling fabrics show limited evaporation capacity when they reach the adsorption limit in intense perspiration scenarios. Herein, a fouling‐proof cooling (FP‐Cool) fabric with an interactive functional structure design for highly‐efficient personal thermal regulation is proposed by constructing spatially distributed superoleophobic Janus channels on an optimized heat conductive superomniphobic fabric. The dominant superomniphobicity and superoleophobic Janus feature endow the outer FP‐Cool fabric with durable performance (up to 3000 cycles' abrasion) to repel oil/water‐based contaminations. The Janus channels rapidly pull sweat out of the inner fabric for efficient evaporation, ensuring a dry sense of skin. The FP‐Cool fabric preserves 40% higher thermal conductivity, and over 50% higher evaporation rate than conventional fabrics. In the sweat evaporation test, the FP‐Cool fabric shows up to 100% reduction in sweat gain ratio to cotton fabric. The concept would have implications for intelligent textiles design, and the synthesis strategy can be applied in various applications such as oil‐water separation and microfluidics control. [ABSTRACT FROM AUTHOR]

Selective-superwetting membranes possess controllable wettability and have great potential in the oil–water (OW) separation field. The electrospinning technique has advantages in fabricating nanofibrous materials with distinguishing features such as high porosity and large surface area. However, in recent years, there have been a few studies on preparing photoinduced superwetting membranes by electrospinning. In this study, an ultraviolet-driven selective-superwetting nanofibrous membrane was prepared by electrospinning poly-(vinylidene fluoride)-cohexafluoropropylene (PVDF-HFP) blended with fluorinated TiO2 nanoparticles. The wetting behavior of the membrane can be tuned between superhydrophobic/superoleophilic and superhydrophilic/underwater superoleophobic by two processes, ultraviolet (UV) irradiation, and heating, during which the water contact angle (WCA) fluctuates rapidly from 170 to 0° and back to 160°. The reliability of the controllable wettability was proven by a 15-cycle conversion test, and the nanofibrous membrane remained superhydrophobic thereafter. Our results have promising multipurpose applications as an effective and flexible solution to more complex oil–water mixtures in wastewater abatement. [ABSTRACT FROM AUTHOR]

Solid materials ubiquitously suffer from oil fouling in engineering applications. In this work, a facile and economical method was proposed to prepare a substrate-independent self-cleaning coating with remarkable oil repellency, which were realized by dints of the surface of nanocomposite structures with polar groups introduced by silica nanoparticles and polydopamine. The dip coating preparation process can be carried out in an ambient atmosphere without the use of hazardous reagents or complex equipment. The coating displays self-cleaning performance to detach the adhered oil after being immersed into water. The underwater contact angles were measured over 150° to various oils, further retaining stability in corrosive aqueous environments. Moreover, the coated glass shows resistance to water condensation, which can remain transparent after steaming or frosting, due to its hydrophilicity. The special wettability also endows the coated fabric with permselectivity to water and oil. Modified filter cotton was utilized to separate five kinds of oil/water mixtures. This study proposed a tried-and-true approach to realize oil repellency. It is anticipated that it could set a precedent for the design of self-cleaning or antifouling coatings. [ABSTRACT FROM AUTHOR]