Superwetting Ag/α-Fe_(2)O_(3) anchored mesh with enhanced photocatalytic and antibacterial activities for efficient water purification

Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice.

Simultaneously spray-assisted assembling reversible superwetting coatings for oil-water separation

Here,superhydrophobic cuprous oxide(Cu2O)with hierarchical micro/nanosized structures was synthesized via sprayassisted layer by layer assembling.The asprepared superhydrophobic meshes with high contact angle(159.6°)and low sliding angle(1°)are covered with Cu_(2)O "coral reef"like micro/nanosized structures.Interestingly,the superhydrophobic mesh surfaces became superhydrophilic again due to the oxidization of Cu_(2)O to CuO by annealing at a higher temperature(300℃).And the superhydrophobic properties would be recovered by heating at 120℃.Furthermore,the superwetting meshes were applied to design a miniature device to separate light or heavy oil from the wateroil mixtures with excellent separation efficiency.These superwetting surfaces by simultaneously sprayassisted layer by layer assembling technique show the potential application in universal oilwater separation.

Highly catalytic metal–organic framework coating enabled by liquid superwetting and confinement

In this work,we report that high catalytic performance of metal–organic frameworks(MOFs)can be obtained through a synergistic effect of postsynthetic modification of MOF nanoparticles and liquid superwetting and confinement in the MOF coating.Specifically,2-ureido-4[1H]pyrimidinone(UPy)functionalized polysiloxanes were covalently appended onto the UiO-66 nanoparticles via a postsynthetic approach,which were further anchored onto different porous films through multivalent hydrogen bonding of the UPy motifs.The hydrophobic MOF coating can preserve the porosity of the solid substrates,enable rapid liquid superwetting and confinement within the porous substrates.Using the Knoevenagel condensation as a modeled system,robust and highly catalytic performances of the MOF coating were observed on a range of aldehyde substrates.Gram-scale production of chromene,a pharmaceutical which is typically synthesized via expensive catalysis,was successfully demonstrated on the MOF coating with high yielding rates,demonstrating the great potential of the MOF coating in pharmaceutical synthesis.

A Versatile Coating Approach to Fabricate Superwetting Membranes for Separation of Water-in-Oil Emulsions

Separation of oil/water mixtures, especially for the emulsified oil/water mixtures, is important because of the frequent occurrence of oil spill accidents. Utilizing superwetting porous membrane has become a promising approach to separate either surfactant-free or surfactant-stabilized emulsions. Herein we report a facile and versatile strategy for preparing hydrophobic/under-oil superhydrophobic membranes by coating the skeletons of the membranes with the poly[（3,3,3- trifluoropropyl）methylsiloxane] （PTFPMS） nanoparticles. The obtained membranes could be used to separate various water- in-oil emulsions with high flux and separation efficiency. In addition, owning to the outstanding resistance of PTFPMS to the most organic solvents or oils, the modified membranes exhibited the excellent reusability and the antifouling properties that were critical in the practical applications. Many commercially available membranes can be modified by such a simple method.

Hierarchical metal-phenolic-polyplex assembly toward superwetting membrane for high-flux and antifouling oil-water separation

Superwetting membranes have emerged as promising materials for the efficient treatment of oily wastewater.Typically,superwetting membranes can be developed by ingeniously chemical modification and topographical structuration of microporous membranes.Herein,we report the hierarchical assembly of metal-phenolic-polyplex coating to manipulate membrane surface superwettability by integrating metal-phenolic(Fe^(Ⅲ)-tannic acid(TA))assembly with polyplex(tannic acid-polyethylenimine(PEI))assembly.The proposed Fe-TA-PEI coating can be deposited on microporous membrane via simply dipping into Fe^(Ⅲ)-TA-PEI co-assembly solution.Based on the catechol chemistry,the coordination complexation of Fe^(Ⅲ)and TA develops metal-phenolic networks to provide hydrophilic chemistries,and the electrostatic complexation of TA and PEI generates nanoconjugates to impart hierarchical architectures.Benefiting from the synergy of hydrophilic chemistries and hierarchical architectures,the resulting PVDF/Fe-TA-PEI membrane exhibits excellent superhydrophilicity(~0°)underwater superoleophobicity(~150°)and superior anti-oil-adhesion capability.The superhydrophilicity of PVDF/Fe-TA-PEI membrane greatly promotes membrane permeability,featuring water fluxes up to 5860 L m^(-2)h^(-1).The underwater superoleophobicity of PVDF/Fe-TA-PEI membrane promises potential flux(3393 L m^(-2)h^(-1)),high separation efficiency(99.3%)and desirable antifouling capability for oil-in-water emulsion separation.Thus,we highlight the reported hierarchical metal-phenolic-polyplex assembly as a straightforward and effective strategy that enables the synchronous modulation of surface chemistry and topography toward superwetting membranes for promising high-flux and antifouling oil-water separation.

Superwetting polyethersulfone membrane functionalized with ZrO_(2) nanoparticles for polycyclic aromatic hydrocarbon removal

Polycyclic aromatic hydrocarbons(PAHs)are persistent and widespread in the aquatic environment,causing potential hazards for human health.In this study,a superwetting and robust PES-PAA-ZrO_(2)nanofiltration membrane was proposed through surface modification for PAH removal with high efficiency.A ZrO_(2)coating was formed on polyethersulfone(PES)membrane surface through chemical bonding,thus the PES-PAA-ZrO_(2)membrane exhibited super-hydrophilicity,under-water oleophobicity,and excellent stability.In comparison with the original PES membrane,the water contact angle of the modified membrane was significantly decreased from about 50°to less than 10°,and quickly dropped to 0°within 1s.This provided a much lower energy barrier for water permeation due to its super-high water affinity.The wastewater treatment efficiency was increased by about 4 times after modification with more than 90%of PAH rejection rate.The excellent robustness of PES-PAA-ZrO_(2)membrane was verified under various conditions,which gave the membrane practical potential for long-term operation.

Highly transparent and super-wettable nanocoatings hybridized with isocyanate-silane modified surfactant for multifunctional applications

Highly transparent and super-wettable nanocoatings for multifunctional applications with outstanding physical properties are in high demanded.However,such nanocoatings resistant to water invasion and Ultraviolet(UV)weathering remain a significant challenge.In this work,physically durable coatings based on inorganic nanoparticles(NPs)and an organic segment(isocyanate-silane modified surfactant)have been synthesized via a sol-gel approach.It is noteworthy the isocyanate-silane with-NH-C=O-functional group creates a strong bonding between the highly hydrophilic surfactant and the inorganic NPs.This in-house synthesized organic segment can render the coating long-lasting wetting properties and resist to be washed away by water,while the inorganic NPs can form sturdy covalent bonds with the nano-scale hierarchical structure on the glazing substrate to improve the durability.This nanocoating demonstrates high transparency with superwetting property(water contact angle,WCA=4.4±0.3°),effective de-frosting performance.Water invasion or UV accelerated weathering tests do not significantly affect the self-cleaning performance of nanocoating.Physical properties,including coating adhesion,hardness,Young's modulus,and abrasion resistance are systematically investigated.Interestingly,this clear coating shows prominent infrared shielding property attributed to Antimony-doped tin oxide(Sb-doped SnO_(2))NPs.The developed nanocoating process is easy to scale up for larger areas that require multipurpose self-cleaning functions.

Effective purification of oily wastewater using lignocellulosic biomass:A review

Due to the frequent occurrence of oil spills and the large-scale production of oily wastewater, the treatment of oily sewage has become an important issue for sustainable development. Recently, materials prepared from lignocellulosic biomass(LCB) for oil-water separation have been found to be effective due to their high separation efficiency, good recyclability, and superior sustainability. However, few reviews have focused on the advantages and limitations of LCB for sewage treatment. This review summarizes the performance of modified LCB in oily wastewater treatment, in terms of the advanced modification methods applied and the structural dimensions of LCB materials according to the principle of superwetting oil-water separation. Research on the preparation technologies, separation mechanisms, and treatment efficiency of different LCB materials are briefly summarized, along with the characteristics of different LCB material types for oily wastewater treatment. Finally, the future prospects and challenges faced in the development of LCB materials are discussed.

基于形状记忆海绵的“门控”液体二极管

超浸润Janus膜因其独特的单向液体输送能力,被称为“液体二极管”,引起了人们的广泛关注.近年来,赋予Janus膜智能可控性成为一个新的研究热点.然而,相关的报道仍然很少,且限于调节表面浸润性方面,这很难避免一些局限性,如需要恒定外部刺激和特定的水溶液.在此,我们提出了一种通过调节材料的孔结构来智能控制液体在Janus膜上渗透的新策略,并报告了一种由超亲水海绵(SHS)和疏水形状记忆海绵(HSMS)构成的智能Janus海绵(SJS).基于良好的形状记忆效应,HSMS的孔径和厚度可以在压缩/回复状态之间可逆地改变.随着HSMS的变化,水的渗透可以得到巧妙地控制,这体现在只有在HSMS处于压缩状态时,SJS才呈现“液体二极管”的效果,否则将防止液体从两侧渗透.最后,基于SJS的智能可控性,我们模拟了换药场景,展示了其在伤口敷料领域的潜在应用.本工作首次报道了一种形状记忆Janus膜,为控制液体渗透提供了一种新的方法,成功地避免了现有浸润性响应Janus膜存在的缺点.鉴于其良好的可控性,我们相信它在液体智能操纵方面有潜在的应用.