Oil sorbents play a very important part in the remediation processes of oil spills. To enhance the oil-sorption properties and simplify the oil-recovery process, various advanced oil sorbents and oil-collecting devices based on them have been proposed recently. Here, we firstly discuss the design considerations for the fabrication of oil sorbents and describe recently developed oil sorbents based on modification strategy. Then, recent advances regarding oil sorbents mainly based on carbon materials and swellable oleophilic polymers are also presented. Subsequently, some additional properties are emphasized, which are required by oil sorbents to cope with oil spills under extreme conditions or to facilitate the oil-collection processes. Furthermore, some oil-collection devices based on oil sorbents that have been developed recently are shown. Finally, an outlook and challenges for the next generation of oil-spill-remediation technology based on oil-sorbents materials are given.

A stretchable and multiple-force-sensitive electronic fabric based on stretchable coaxial sensor electrodes is fabricated for artificial-skin application. This electronic fabric, with only one kind of sensor unit, can simultaneously map and quantify the mechanical stresses induced by normal pressure, lateral strain, and flexion.

The clean-up of viscous crude-oil spills is a global challenge. Hydrophobic and oleophilic oil sorbents have been demonstrated as promising candidates for oil-spill remediation. However, the sorption speeds of these oil sorbents for viscous crude oil are rather limited. Herein we report a Joule-heated graphene-wrapped sponge (GWS) to clean-up viscous crude oil at a high sorption speed. The Joule heat of the GWS reduced in situ the viscosity of the crude oil, which prominently increased the oil-diffusion coefficient in the pores of the GWS and thus speeded up the oil-sorption rate. The oil-sorption time was reduced by 94.6% compared with that of non-heated GWS. Besides, the oil-recovery speed was increased because of the viscosity decrease of crude oil. This in situ Joule self-heated sorbent design will promote the practical application of hydrophobic and oleophilic oil sorbents in the clean-up of viscous crude-oil spills.

Unidirectional underwater gas bubble (UGB) transport on a surface is realized by buoyant force or wettability gradient force (F wet-grad ) derived from a tailored geography. Unfortunately, intentional control of the UGB over transport speed, direction, and routes on horizontal planar surfaces is rarely explored. Herein reported is a light-responsive slippery lubricantinfused porous surface (SLIPS) composed of selective lubricants and super-hydrophobic micropillar-arrayed Fe 3 O 4 /polydimethylsiloxane film. Upon this SLIPS, the UGB can be horizontally actuated along arbitrary directions by remotely loading/discharging unilateral near-infrared (NIR) stimuli. The underlying mechanism is that F wet-grad can be generated within 1 s in the presence of a NIR-trigger due to the photothermal effect of Fe 3 O 4 . Once the NIR-stimuli are discharged, F wet-grad vanishes to break the UGB on the SLIPS. Moreover, performed are systematic para meter studies to investigate the influence of bubble volume, lubricant rheology, and F wet-grad on the UGB steering performance. Fundamental physics renders the achievement of antibuoyancy manipulation of the UGBs on an inclined SLIPS. Significantly, steering UGBs by horizontal SLIPS to configurate diverse patterns, as well as facilitating light-control-light optical shutter, is deployed. Compared with the previous slippery surfaces, light-responsive SLIPS is more competent for manipulating UGBs with controllable transport speed, direction, and routes independent of buoyancy or geography derivative force.

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Achieving the unidirectional transportation of bubbles in the liquid phase is of great importance for solving both academic and industrial issues. Here, Janus (hydrophobic and superhydrophobic surfaces) microhole‐arrayed polydimethylsiloxane fabricated by one‐step femtosecond laser drilling for ultrafast underwater bubble unidirectional transportation is reported. In aqueous solution, bubbles selectively penetrate from an aerophilic side to a superaerophilic one in the direction of both buoyancy and antibuoyancy, but are blocked in a reverse direction. More importantly, the bubbles readily penetrate through this Janus system within 81 ms, which is two orders of magnitude shorter than that of a previous Janus one because the aerophilic surface of current Janus system is more favorable for capturing and transporting the bubble than the superaerophobic surface of Janus system. Additionally, this “diode” presents a switchable property, which is dependent on the laser exposure dosage. According to X‐ray photoelectron spectroscopy spectrum, the underlying mechanism is that the excessive laser exposure dosage is inclined to induce the graft of oxyhydryl group as the substitution of the original hydrocarbyl group. This work may provide an innovatory insight for designing advanced materials for ultrafast gas bubble directional transportation/collection in aqueous media, in addition to gas/liquid separation.

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The photoinduced manipulation of liquids on a slippery lubricant-infused porous surface (SLIPS) has attracted a tremendous amount of attention because of its merits of contactless stimulation and excellent spatial and temporal control. However, tedious fabrication methods by a combination of template transfer and fluorination for a photothermal-material-doped SLIPS and the lack of deeper systematically quantitative analysis with respect to droplet hydrokinetics are greatly perplexing in both academic research and industrial applications. Here we demonstrate a kind of Fe 3 O 4 -doped SLIPS by one-step femtosecond laser cross-scanning, which can readily steer diverse liquids toward arbitrary directions with a fast velocity of up to 1.15 mm/s in the presence of a unilateral NIR stimulus. The underlying mechanism is that the wettability gradient force (F wet-grad ) induced by the temperature gradient arising from asymmetric near-infrared-irradiation (NIR) loading would be generated within 1 s to actuate a targeted droplet's sliding behavior. Through tuning the NIR irradiating sites, we can slide a targeted droplet with controllable directions and routes. On the basis of fundamental physics, we have quantitatively analyzed the relationship among Fe 3 O 4 -doped content, lubricant rheological performance, droplet wettability variations, F wet-grad , and the sliding velocity for diverse liquid species. Accordingly, we can remotely steer liquid droplets to realize the on−off state of an electrical circuit on demand, the droplet fusion of a microfluidic reactor, and the culture/inhibition of biological cells.