In order to satisfy the needs of different applications and more complex intelligent devices,smart control of surface wettability will be necessary and desirable,which gradually become a hot spot and focus in the fiel...In order to satisfy the needs of different applications and more complex intelligent devices,smart control of surface wettability will be necessary and desirable,which gradually become a hot spot and focus in the field of interface wetting.Herein,we review interfacial wetting states related to switchable wettability on superwettable materials,including several classical wetting models and liquid adhesive behaviors based on the surface of natural creatures with special wettability.This review mainly focuses on the recent developments of the smart surfaces with switchable wettability and the corresponding regulatory mechanisms under external stimuli,which is mainly governed by the transformation of surface chemical composition and geometrical structures.Among that,various external stimuli such as physical stimulation(temperature,light,electric,magnetic,mechanical stress),chemical stimulation(pH,ion,solvent)and dual or multi-triggered stimulation have been sought out to realize the regulation of surface wettability.Moreover,we also summarize the applications of smart surfaces in different fields,such as oil/water separation,programmable transportation,anti-biofouling,detection and delivery,smart soft robotic etc.Furthermore,current limitations and future perspective in the development of smart wetting surfaces are also given.This review aims to offer deep insights into the recent developments and responsive mechanisms in smart biomimetic surfaces with switchable wettability under external various stimuli,so as to provide a guidance for the design of smart surfaces and expand the scope of both fundamental research and practical applications.展开更多
The large number of oily wastewater discharges and oil spills are bringing about severe threats to environment and human health.Corresponding to this challenge,a functional PAA-ZnO-HDTMS flax fiber with UV-induced swi...The large number of oily wastewater discharges and oil spills are bringing about severe threats to environment and human health.Corresponding to this challenge,a functional PAA-ZnO-HDTMS flax fiber with UV-induced switchable wettability was developed for efficient oil-water separation in this study.The developed flax fiber was obtained through PAA grafted polymerization and then ZnO-HDTMS nanocomposite immobilization.The as-prepared PAA-ZnO-HDTMS flax fiber was hydrophobic initially and could be switched to hydrophilic through UV irradiation.Its hydrophobicity could be easily recovered through being stored in dark environment for several days.To optimize the performance of the PAA-ZnO-HDTMS flax fiber,the effects of ZnO and HDTMS concentrations on its switchable wettability were investigated.The optimized PAA-ZnO-HDTMS flax fiber had a large water contact angle(∼130°)in air and an extremely small oil contact angle(∼0°)underwater initially.After UV treatment,the water contact angle was decreased to 30°,while the underwater oil contact angle was increased to more than 150°.Based on this UV-induced switchable wettability,the developed PAA-ZnO-HDTMS flax fiber was applied to remove oil from immiscible oil-water mixtures and oil-in-water emulsion with great reusability for multiple cycles.Thus,the developed flax fiber could be further fabricated into oil barrier or oil sorbent for oil-water separation,which could be an environmentally-friendly alternative in oil spill response and oily wastewater treatment.展开更多
In this study, an effective method is proposed for controlling a titanium foil surface's wettability. A microholes array series is fabricated on the surface of titanium foil by a femtosecond laser under different ...In this study, an effective method is proposed for controlling a titanium foil surface's wettability. A microholes array series is fabricated on the surface of titanium foil by a femtosecond laser under different laser energy and pulse number. The changes of the titanium surface's morphology are characterized. When placed in a darkroom with high-temperature treatment and immersed in alcohol under UV irradiation, respectively, the femtosecond laser treated surfaces display switchable wettability. It is demonstrated that the changing between Ti-OH and Ti-O prompts the transformation between superhydrophilic and superhydrophobic. Compared with existing reports, the switchable wetting cycle is shortened to 1.5 h. The functional surfaces with switchable wettability have potential applications in oil–water separation and water mist collection.展开更多
We fabricated pH and light dual-responsive adsorption materials which could induce the transition of surface wettability between hydrophobicity and hydrophilicity by using ATRPo The structure and morphology of adsorpt...We fabricated pH and light dual-responsive adsorption materials which could induce the transition of surface wettability between hydrophobicity and hydrophilicity by using ATRPo The structure and morphology of adsorption materials were confirmed by ATR-FTIR, XPS, TGA and SEM. It showed that the modified cellulose （CE）- based foam was hydrophobic, which can adsorb a range of oils and organic solvents in water under pH = 7.0 or visible light irradiation （λ〉500 nm）. Meanwhile, the wettability of robust CE-based foam can convert hydrophobicity into hydrophilicity and underwater oleophobicity under pH = 3.0 or UV irradiation （λ = 365 nm）, giving rise to release oils and organic solvents. Most important of all, the adsorption and desorption processes of the modified CE-based foam could be switched by external stimuli. Furthermore, the modified CE-based foam was not damaged and still retained original performance after reversible cycle repeated for many times with variation of surface wettability. In short, it indicates that CE-based foam materials with switchable surface wettability are new responsive absorbent materials and have owned potential application in the treatment of oil recovery.展开更多
基金The authors thank the National Natural Science Foundation of China(No.51775231)National Postdoctoral Program for Innovative Talents(BX20180123)+2 种基金China Postdoctoral Science Foundation(2018M641782)Scientific Research Project of Jilin Provincial Department of Education(JJKH20211117KJ)JLU Science and Technology Innovative Research Team(No.2017TD-04).
文摘In order to satisfy the needs of different applications and more complex intelligent devices,smart control of surface wettability will be necessary and desirable,which gradually become a hot spot and focus in the field of interface wetting.Herein,we review interfacial wetting states related to switchable wettability on superwettable materials,including several classical wetting models and liquid adhesive behaviors based on the surface of natural creatures with special wettability.This review mainly focuses on the recent developments of the smart surfaces with switchable wettability and the corresponding regulatory mechanisms under external stimuli,which is mainly governed by the transformation of surface chemical composition and geometrical structures.Among that,various external stimuli such as physical stimulation(temperature,light,electric,magnetic,mechanical stress),chemical stimulation(pH,ion,solvent)and dual or multi-triggered stimulation have been sought out to realize the regulation of surface wettability.Moreover,we also summarize the applications of smart surfaces in different fields,such as oil/water separation,programmable transportation,anti-biofouling,detection and delivery,smart soft robotic etc.Furthermore,current limitations and future perspective in the development of smart wetting surfaces are also given.This review aims to offer deep insights into the recent developments and responsive mechanisms in smart biomimetic surfaces with switchable wettability under external various stimuli,so as to provide a guidance for the design of smart surfaces and expand the scope of both fundamental research and practical applications.
基金supported by the Natural Science and Engineering Research Council of Canada,the Canada Foundation for Innovation(CFI)(36668)the Canada Research Chairs Program(CRC),the Western Diversification Program(Canada)(15269)the Petroleum Technology Research Centre.
文摘The large number of oily wastewater discharges and oil spills are bringing about severe threats to environment and human health.Corresponding to this challenge,a functional PAA-ZnO-HDTMS flax fiber with UV-induced switchable wettability was developed for efficient oil-water separation in this study.The developed flax fiber was obtained through PAA grafted polymerization and then ZnO-HDTMS nanocomposite immobilization.The as-prepared PAA-ZnO-HDTMS flax fiber was hydrophobic initially and could be switched to hydrophilic through UV irradiation.Its hydrophobicity could be easily recovered through being stored in dark environment for several days.To optimize the performance of the PAA-ZnO-HDTMS flax fiber,the effects of ZnO and HDTMS concentrations on its switchable wettability were investigated.The optimized PAA-ZnO-HDTMS flax fiber had a large water contact angle(∼130°)in air and an extremely small oil contact angle(∼0°)underwater initially.After UV treatment,the water contact angle was decreased to 30°,while the underwater oil contact angle was increased to more than 150°.Based on this UV-induced switchable wettability,the developed PAA-ZnO-HDTMS flax fiber was applied to remove oil from immiscible oil-water mixtures and oil-in-water emulsion with great reusability for multiple cycles.Thus,the developed flax fiber could be further fabricated into oil barrier or oil sorbent for oil-water separation,which could be an environmentally-friendly alternative in oil spill response and oily wastewater treatment.
基金supported by the National Key R&D Program of China (No.2017YFB1104300)the National Natural Science Foundation of China (No.51975595)+1 种基金the Natural Science Foundation of Hunan Province (No.2020JJ5738)the Project of State Key Laboratory of High Performance Complex Manufacturing (No.ZZYJKT2020-10)。
文摘In this study, an effective method is proposed for controlling a titanium foil surface's wettability. A microholes array series is fabricated on the surface of titanium foil by a femtosecond laser under different laser energy and pulse number. The changes of the titanium surface's morphology are characterized. When placed in a darkroom with high-temperature treatment and immersed in alcohol under UV irradiation, respectively, the femtosecond laser treated surfaces display switchable wettability. It is demonstrated that the changing between Ti-OH and Ti-O prompts the transformation between superhydrophilic and superhydrophobic. Compared with existing reports, the switchable wetting cycle is shortened to 1.5 h. The functional surfaces with switchable wettability have potential applications in oil–water separation and water mist collection.
基金This work was supported financially by funding from the National Natural Science Foundation of China （Grant Nos. 21367022 and 51662036） and the Bingtuan Innovation Team in Key Areas （2015BD003）.
文摘We fabricated pH and light dual-responsive adsorption materials which could induce the transition of surface wettability between hydrophobicity and hydrophilicity by using ATRPo The structure and morphology of adsorption materials were confirmed by ATR-FTIR, XPS, TGA and SEM. It showed that the modified cellulose （CE）- based foam was hydrophobic, which can adsorb a range of oils and organic solvents in water under pH = 7.0 or visible light irradiation （λ〉500 nm）. Meanwhile, the wettability of robust CE-based foam can convert hydrophobicity into hydrophilicity and underwater oleophobicity under pH = 3.0 or UV irradiation （λ = 365 nm）, giving rise to release oils and organic solvents. Most important of all, the adsorption and desorption processes of the modified CE-based foam could be switched by external stimuli. Furthermore, the modified CE-based foam was not damaged and still retained original performance after reversible cycle repeated for many times with variation of surface wettability. In short, it indicates that CE-based foam materials with switchable surface wettability are new responsive absorbent materials and have owned potential application in the treatment of oil recovery.
