Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels...Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels with excellent environmental stability,efficient room-temperature self-healing and recyclability properties,as well as amphiphobic slippery surfaces,are fabricated by incorporating binary ionic liquids into a rationally designed self-healing polyurethane with perfluoroalkyl side chains.The outstanding and stable thermochromic performance of the resulting ionogels stems from the hydrogen bond-mediated,confined,and reversible phase separation of ionic liquids within the polyurethane network,enabling the ionogels to effectively reduce indoor temperatures and enhance the comfort of occupants.The surface-enriched perfluoroalkyl side chains enable various liquids,including water,alkanes,and edible oils,to easily slide off the ionogel surface without leaving any residue,preventing the transmittance decrease and thermochromic performance degradation caused by contaminations.The dynamic hydrogen bonds within the polyurethane network enable the ionogels to repeatedly heal physical and chemical damages,as well as to be recycled multiple times without performance loss,thereby reducing maintenance costs and minimizing material waste.This study provides a novel approach to developing advanced thermochromic materials for smart windows,potentially improving the building energy efficiency and sustainability.展开更多
In membrane distillation(MD),complicated feed water with amphiphilic contaminants induces fouling/wetting of the MD membrane and can even lead to process failure.This study reports a facile approach to fabricate robus...In membrane distillation(MD),complicated feed water with amphiphilic contaminants induces fouling/wetting of the MD membrane and can even lead to process failure.This study reports a facile approach to fabricate robust and self-healing hybrid amphiphobic membranes for anti-surfactant-wetting MD based on the ultra-low surface energy of fluorinated polyhedral oligomeric silsesquioxanes(F-POSS)and its thermal induced motivation and rotation.The thermal treatment makes the membranes achieving amphiphobicity at a very low cost of F-POSS(13.04 wt.%),which is about 1/3 of without thermal treatment.The prepared membrane exhibits excellent amphiphobicity,i.e.ethanol contact angle of 120.3°,without using environmentally toxic fluorinated nanoparticles.Robust MD performance was observed for the amphiphobic membrane in concentrated sodium dodecyl sulfate(SDS)feed solutions.Furthermore,the fabricated membrane exhibited stable amphiphobicity even in extreme environments,including strong acid or alkaline solutions.In the event of a damaged or abraded membrane surface where the F-POSS can be removed,the amphiphobic membrane exhibits self-healing ability with additional thermal treatment.This simple approach without the use of nanoparticles provides an environmentally friendly way for fabrication of amphiphobic membranes for anti-surfactant-wetting membrane distillation.展开更多
Discharging untreated oily wastewater into the environment disrupts the ecological balance,which is a global problem that requires urgent solutions.Superhydrophilic and superoleophilic fibrous medium(FM)effectively se...Discharging untreated oily wastewater into the environment disrupts the ecological balance,which is a global problem that requires urgent solutions.Superhydrophilic and superoleophilic fibrous medium(FM)effectively separated oil–water emulsion as it was hydrophobic underwater.But its separation efficiencies(SEs)first increased to 98.9%,then dropped to 97.6%in 10 min because of oil-fouling.To tackle this problem,FM deposited with 0%–10%silica nanoparticle(NPsFMs),then coated by fluorocarbon polymer(X-[CH_(2)CH_(2)O]nCH_(2)CH_(2)O-Y-NH-COOCH_(2)C4F9)(FCNPs FMs),was used to enhance its roughness and regulate its initial wettability to improve the anti-fouling property.FCFM and FCNPs FMs were hydrophobic and oleophobic in air and oleophobic underwater.Their water contact angles,oil contact angles and oil contact angles were 115.3°–121.1°,128.8°–136.5°,and 131.6°–136.7°,respectively,meeting the requirement of 90°–140°for coalescence separation.FCNPs FM-5 had the best separation performance with a constant value of 99.8%in 10 min,while that of FCNPs FM-10 slightly decreased to 99.5%.Theoretical released droplet(TRD)diameter,calculated by the square root of the product of pore radius and fiber diameter,was used for the evaluation of coalescence performance.Analyzed by two ideal models,TRD diameter and fiber diameter showed a parabola type relationship,proving that the separation efficiency was a collaborative work of wettability,pore size and fiber diameter.Also,it explained the SEs reduction from FCNPs FM-5 to FCNPs FM-10 was revelent to the three parameters.Moreover,FCNPsFMs effectively separated emulsions stabilized by cationic surfactant CTAB(SEs:97.3%–98.4%)and anionic surfactant SDBS(SEs:91.3%–93.4%).But they had an adverse effect on nonionic surfactant Tween-80 emulsion separation(SEs:94.0%–71.76%).Emulsions made by diverse oils can be effectively separated:octane(SEs:99.4%–100%),rapeseed oil(SEs:97.3%–98.8%),and diesel(SEs:95.2%–97.0%).These findings provide new insights for designing novel materials for oil–water separation by coalescence mechanism.展开更多
基金supported by the National Natural Science Foundation of China(22475082,21971083)。
文摘Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels with excellent environmental stability,efficient room-temperature self-healing and recyclability properties,as well as amphiphobic slippery surfaces,are fabricated by incorporating binary ionic liquids into a rationally designed self-healing polyurethane with perfluoroalkyl side chains.The outstanding and stable thermochromic performance of the resulting ionogels stems from the hydrogen bond-mediated,confined,and reversible phase separation of ionic liquids within the polyurethane network,enabling the ionogels to effectively reduce indoor temperatures and enhance the comfort of occupants.The surface-enriched perfluoroalkyl side chains enable various liquids,including water,alkanes,and edible oils,to easily slide off the ionogel surface without leaving any residue,preventing the transmittance decrease and thermochromic performance degradation caused by contaminations.The dynamic hydrogen bonds within the polyurethane network enable the ionogels to repeatedly heal physical and chemical damages,as well as to be recycled multiple times without performance loss,thereby reducing maintenance costs and minimizing material waste.This study provides a novel approach to developing advanced thermochromic materials for smart windows,potentially improving the building energy efficiency and sustainability.
基金the National Key Research and Development Program of China(No.2016YFB0600501)Natural Science Foundation of China(Nos.51425405 and 21377130)China Scholarship Council(No.201804910753)。
文摘In membrane distillation(MD),complicated feed water with amphiphilic contaminants induces fouling/wetting of the MD membrane and can even lead to process failure.This study reports a facile approach to fabricate robust and self-healing hybrid amphiphobic membranes for anti-surfactant-wetting MD based on the ultra-low surface energy of fluorinated polyhedral oligomeric silsesquioxanes(F-POSS)and its thermal induced motivation and rotation.The thermal treatment makes the membranes achieving amphiphobicity at a very low cost of F-POSS(13.04 wt.%),which is about 1/3 of without thermal treatment.The prepared membrane exhibits excellent amphiphobicity,i.e.ethanol contact angle of 120.3°,without using environmentally toxic fluorinated nanoparticles.Robust MD performance was observed for the amphiphobic membrane in concentrated sodium dodecyl sulfate(SDS)feed solutions.Furthermore,the fabricated membrane exhibited stable amphiphobicity even in extreme environments,including strong acid or alkaline solutions.In the event of a damaged or abraded membrane surface where the F-POSS can be removed,the amphiphobic membrane exhibits self-healing ability with additional thermal treatment.This simple approach without the use of nanoparticles provides an environmentally friendly way for fabrication of amphiphobic membranes for anti-surfactant-wetting membrane distillation.
基金supported by the National Key Research and Development Program of China under the contract number of 2017YFB0308000Program of Innovation Academy for Green Manufacture,CAS(IAGM2020C04)+1 种基金the State Key Laboratory of Heavy Oil Processing(SKLOP201903001)Key Research and Development Program of Hebei Province,China(20374001D)。
文摘Discharging untreated oily wastewater into the environment disrupts the ecological balance,which is a global problem that requires urgent solutions.Superhydrophilic and superoleophilic fibrous medium(FM)effectively separated oil–water emulsion as it was hydrophobic underwater.But its separation efficiencies(SEs)first increased to 98.9%,then dropped to 97.6%in 10 min because of oil-fouling.To tackle this problem,FM deposited with 0%–10%silica nanoparticle(NPsFMs),then coated by fluorocarbon polymer(X-[CH_(2)CH_(2)O]nCH_(2)CH_(2)O-Y-NH-COOCH_(2)C4F9)(FCNPs FMs),was used to enhance its roughness and regulate its initial wettability to improve the anti-fouling property.FCFM and FCNPs FMs were hydrophobic and oleophobic in air and oleophobic underwater.Their water contact angles,oil contact angles and oil contact angles were 115.3°–121.1°,128.8°–136.5°,and 131.6°–136.7°,respectively,meeting the requirement of 90°–140°for coalescence separation.FCNPs FM-5 had the best separation performance with a constant value of 99.8%in 10 min,while that of FCNPs FM-10 slightly decreased to 99.5%.Theoretical released droplet(TRD)diameter,calculated by the square root of the product of pore radius and fiber diameter,was used for the evaluation of coalescence performance.Analyzed by two ideal models,TRD diameter and fiber diameter showed a parabola type relationship,proving that the separation efficiency was a collaborative work of wettability,pore size and fiber diameter.Also,it explained the SEs reduction from FCNPs FM-5 to FCNPs FM-10 was revelent to the three parameters.Moreover,FCNPsFMs effectively separated emulsions stabilized by cationic surfactant CTAB(SEs:97.3%–98.4%)and anionic surfactant SDBS(SEs:91.3%–93.4%).But they had an adverse effect on nonionic surfactant Tween-80 emulsion separation(SEs:94.0%–71.76%).Emulsions made by diverse oils can be effectively separated:octane(SEs:99.4%–100%),rapeseed oil(SEs:97.3%–98.8%),and diesel(SEs:95.2%–97.0%).These findings provide new insights for designing novel materials for oil–water separation by coalescence mechanism.
