Good Self-cleaning Performance Research Articles

RbxCsyWO3 based superhydrophobic transparent thermal insulation film for energy saving

Superhydrophobic transparent insulation film has attracted more attentions in the field of energy-saving glass due to its excellent near-infrared (NIR) shielding property and good self-cleaning performance. In this study, Rb+, Cs+ co-doped tungsten bronze powders were synthesized through a solvothermal reaction, and the superhydrophobic transparent thermal insulation film was constructed on glass. Results show that the strategy of Rb+, Cs+ co-doping can improve the NIR shielding property by incorporating more alkali metal ions into the hexagonal channel and can increase the content of W5+. When n(Rb)/n(Cs)=2, the film exhibits the best NIR shielding performance, with a visible transmittance of 55.6% and an NIR shielding rate of 94.6%. The superhydrophobic tungsten bronze film was successfully prepared with a water contact angle of 163.3±4.1°. The film also exhibits good chemical stability and water impact resistance, with a visible light transmittance of 62.7%, and an NIR shielding rate of 92.9%. The maximum temperature difference in insulation between the uncoated glass and the glass coated with R2WO's PVA/PDMS/SiO2-2 film is 8.9℃ under the irradiation of a tungsten lamp. In conclusion, R2WO's PVA/PDMS/SiO2-2 film, which exhibits excellent heat insulation and good self-cleaning ability, holds great potential for application in the energy-saving glass industry.

Preparation of mixed matrix self-cleaning membrane incorporated by Z-scheme heterostructure via robust engineering in terms of dimension for decreasing cake fouling in a cross-flow reactor

Reducing irreversible fouling in polymer membranes by integrating photocatalytic and membrane processes as the self-cleaning photocatalytic membrane is a promising candidate for improving membrane filtration performance. In this study, mixed matrix photocatalytic membranes were prepared from the combination of different morphologies ZnO-g-C3N4 heterostructure in the polymer matrix by the phase-separation method. To investigate the self-cleaning and performance properties of mixed matrix photocatalytic membranes prepared from different morphologies heterostructures, the photocatalytic membrane reactor with a visible-light source was applied. Nanoflower/nanosheet (NF/NS) ZnO-g-C3N4 photocatalytic membrane showed good self-cleaning performance owing to the high photocatalytic performance of NF/NS ZnO-g-C3N4 heterostructure by the reduction of irreversible membrane fouling, thus improving the antifouling and filtration performance of the membrane. Also, the morphology and the uniform distribution of the NF/NS ZnO-g-C3N4 heterostructure in the membrane matrix caused good hydrophilic properties, high porosity, and a more symmetrical structure in the (NF/NS) ZnO-g-C3N4 photocatalytic membrane (F4). For the F4 membrane, the permeability and rejection values increased from 40.35 L m−2 h−1 and 90.9% in the dark environment to 84.37 L m−2 h−1 and 97.4% under visible-light for dye pollutants. Accordingly, F4 had the best filtration and self-cleaning performance, which can be used as a promising visible-light photocatalytic membrane in wastewater treatment processes.

Nanocellulose-based membranes with pH- and temperature-responsive pore size for selective separation

Smart gating membranes have drawn much attention due to the controllable pore structure. Herein, a smart gating membrane with dual responsiveness was prepared from bacteria cellulose (BC) grafted with pH- and temperature-responsive polymers. By external stimulation, the average pore size of the membrane can be controlled from 33.75 nm to 144.81 nm, and the pure water flux can be regulated from 342 to 2118 L·m−2·h−1 with remarkable variation in the pH range of 1–11 and temperature range of 20–60 °C. The adjustability of pore size is able to achieve the gradient selective separation of particles and polymers with different sizes. In addition, owing to the underwater superoleophobicity and the nanoscale pore structure, the membrane separation efficiencies of emulsified oils are higher than 99 %. Moreover, the controllable pore size endows the membrane with good self-cleaning performance. This nanocellulose-based smart gating membrane has potential applications in the fields of controllable permeation, selective separation, fluid transport, and drug/chemical controlled release systems.

Ultra-low reflection electromagnetic interference shielding nanofiber film with effective solar harvesting and self-cleaning

It is urgent to develop low-reflection electromagnetic interference shielding material to shield electromagnetic waves (EMW) and reduce their secondary radiation pollution. Herein, an electromagnetic interference shielding nanofiber film is composed of ZnO and carbon nanofiber (CNF) via electrospinning and carbonization approachs, and subsequently coating perfuorooctyltriethoxysilane as a protective layer. On the one hand, ZnO coated by porous carbon, which is derived from ZIF-8, endows the nanofiber film low reflection property through optimizing impedance matching between free space and the nanofiber film. On the other hand, the nanofiber film possesses high electromagnetic interference shielding efficiency, which is beneficial by excellent electrical conductivity of CNF derived from waste leather scraps. Furthermore, the nanofiber film involves abundant interface, which contributes to high interfacial polarization loss. Thus, the nanofiber film with a thickness of 250 μm has electrical conductivity of 53 S/m and shielding efficiency of 50 dB. The reflection coefficient of the nanofiber film is inferior to 0.4 indicates that most of EMW are absorbed inside the materials and the nanofiber film is effective in reducing secondary radiation contamination of electromagnetic waves. Fortunately, the nanofiber film exhibits outstanding solar harvesting performance (106 ℃ at 1 sun density) and good self-cleaning performance, which ensure that the nanofiber film can work in harsh environments. This work supplies a credible reference for fabricating low-reflection electromagnetic shielding nanofiber film to reduce secondary radiation pollution and facilitates the upcycling of waste leather scraps.Graphic abstract

Development of UV curable superhydrophobic graphene anti-corrosion coating

This article has developed a super hydrophobic graphene anti-corrosion coating, consisting of fluorinated monomers, UV curable resins, silica, and graphene oxide. The coating does not contain organic solvents and can quickly solidify to form a superhydrophobic anti-corrosion coating. Research has shown that when the crosslinking agent is 3%, the graphene content is 1%, and the silicon dioxide content is greater than 2%, the hydrophobic angle of the coating exceeds 150 °C, and the coating has good self-cleaning performance. The corrosion voltage of the coating after adding graphene and silicon dioxide is -36.5mV, and the corrosion current can reach 1.17 × 10-9A, with the best anti-corrosion performance.

Construction and characterization of superhydrophobic wood coatings using one-step technique

This study was aiming at enhancing the stain resistance and durability of varnish on wood surfaces, a super hydrophobic solution was created by blending the synthetic ZIF-8/paraffin with Hexadecyltrimethoxysilane (HDTMS) at a specified mass ratio. This superhydrophobic mixture was then directly applied onto the wood varnish coating using a one-step method. The microscopic characterization, transmittance, wear resistance, and water contact angle (WCA) tests of hydrophobic coatings indicated that the mass ratio of ZIF-8 to HDTMS affected the surface microstructure and roughness of wood coatings. When the ratio reached 10:1, 5:1, and 2:1, the nanoparticles were dispersed at the interface of the varnish, and the film forming effect was uniform. The transmittance of the varnish coating was about 90%, and the transmittance of the superhydrophobic coating was about 80%. The water absorption rate of the treated sample was much lower than that of the untreated sample. After 10 cycles of abrasion tests, while the WCA decreased, it remained above 150°. Water droplets on the coating surface can remove pollutants through “rolling washing”, demonstrating good self-cleaning performance. The one-step method enables the rapid creation of superhydrophobic films on the surface of wood varnish coating.

A non-fluorinated superhydrophobic PDMS/STA/TiO2 coating with photocatalysis and environmental stability properties by one-step cold spraying

Constructing a titanium dioxide (TiO2) superhydrophobic surface that is both environmentally friendly and long-term stable, while also possessing photocatalytic properties, is a considerable challenge. In this work, instead of a perfluorinated modifier, we used stearic acid (STA) to modify TiO2 nanoparticles. The particles were further utilized to facilitate the rough structure of superhydrophobic surfaces, making these surfaces fluoride-free and environmentally friendly in practical applications. STA/TiO2 nanoparticles and Polydimethylsiloxane (PDMS) were mixed in an ethyl acetate solution to form the PDMS/STA/TiO2 emulsion, which was used to prepare the PDMS/STA/TiO2 coating by a one-step cold spraying. PDMS was introduced into the coating, providing the lower surface energy, adhesiveness, and protection from photo-oxidative damage. It is found that the non-fluorinated PDMS/STA/TiO2 coating exhibits good superhydrophobicity with a water contact angle of 159.7° and a sliding angle of 2.9°. Under ultraviolet (UV) irradiation, the coating displayed excellent photocatalytic degradation activity towards Methylene Blue, Methyl Orange, and Nile Red dyes. Moreover, the coating can withstand sandpaper abrasion, high temperatures and exposure to droplets of different pH values, indicating good chemical, mechanical and thermal stability. The coating presented strong durability, maintaining its superhydrophobicity even after being exposed to air for 3 months or UV irradiation for 5 h. Besides, the coating demonstrates good self-cleaning performance and adaptability. The large-area superhydrophobic surface made by simple and convenient one-step cold spraying is expected to have practical applications in shipbuilding, construction, textiles, and other industries.

Robust and durable self-lubricated surface by facile fabrication for anti-icing/deicing

Undesired ice accumulation can lead to serious negative impacts on daily life and equipment safety. Slippery liquid-infused surfaces (SLISs) have been widely studied for their low ice adhesion strength (τice). However, the lack of durability, weak robustness, and complex preparation process hinder the application of SLISs. In this work, robust oil-infused porous surface (RIPS) was obtained by a facile one-step method, which used epoxy resin (E44) as a substrate and contained fumed silica and silicone oil. The RIPS-6 displays outstanding anti-icing/deicing ability, superior liquid repellency, good self-cleaning performance, and excellent mechanical robustness. At −5 °C, the water droplet remained unfrozen after 7200 s. τice was only 6.9 kPa at −20 °C and remained below 15 kPa during 10 icing cycles. Furthermore, the mixture of E44 and fumed silica enhanced the mechanical properties including the hardness (4 H) and abrasion resistance of RIPS-6. The icephobicity can be remained (τice < 40 kPa) even after 150 cycles of sandpaper abrasion at 2.5 kPa. The anti-icing and deicing coating with excellent mechanical stability and durability significantly improves the practical application possibility of the coating in harsh environments.

Design and performance optimization of self-cleaning coating on decorative UHPC surface

After long-term use, decorative UHPC may adhere to pollutants due to its hydrophilicity, which affects its aesthetics. Due to the smooth and dense exposed surface of UHPC, ordinary self-cleaning coatings have poor adhesion on its surface and are prone to peeling off due to rain wash in the environment, which cannot maintain the self-cleaning performance of UHPC for a long time. In this paper, a modified self-cleaning coating with a double layer structure was designed. The bottom layer is an epoxy resin (ER) adhesive layer to improve the adhesion performance of the coating to UHPC. The surface layer is a polymethylhydrosiloxane (PMHS) modified nano-SiO2 superhydrophobic layer, which satisfies the self-cleaning characteristics while constructing a regular rough superhydrophobic surface on the UHPC surface. The prepared superhydrophobic UHPC showed good self-cleaning performance, with a static water contact angle of 156.5and a sliding angle of only about 2.2. The performance test results show that the double-layer structure design makes the superhydrophobic coating have good wear resistance, water erosion resistance and excellent chemical stability. The surface functional groups, micro-area morphology and roughness were characterized by Fourier transform infrared spectrometer, scanning electron microscopy, optical profiler and atomic force microscopy, respectively. The reasons for the excellent self-cleaning performance and long-term stability of the coating were explained.

Photo-responsive Mn-doped TiO2-based superhydrophobic/ underwater superoleophobicity membrane for efficient oil-water separation and photothermal decontamination

In recent years, oily wastewater has become an important factor in environmental pollution. As a transition metal element, manganese is able to introduce new impurity band gaps using d-orbital hybridization to extend the photoresponse range of TiO2, thus enabling TiO2 to be self-cleaned under UV irradiation more easily. Therefore, we synthesized superhydrophobic/submerged superoleophobic Mn@TiO2-modified membranes which possess a self-cleaning property under UV light using manganese element-doped titanium dioxide and cotton fabric as the substrate by hydrothermal method and then investigated the relevance between the doping concentration of Mn and super-hydrophobicity. The results showed that water contact angles of prepared membranes with the Mn ions doping concentrations of 0.5 mol/L, 1.0 mol/L, and 1.5 mol/L were 147.89°, 150.43°, and 153.37°, respectively. The membrane with 1.5 mol/L was effective for the separation of the dichloromethane-water mixture. Under Xenon lamp irradiation, three membranes with different concentrations showed a significant temperature increase with the maximum rising to 53.1 ℃ within 2 min, reflecting an excellent photothermal conversion capability. In addition, the decontamination ability of the Mn@TiO2 membrane was tested under UV light. The Mn@TiO2 membrane was able to degrade the oil-red solution dripping on the surface, showing that the membrane had a good self-cleaning performance, which was significant for industrial applications.

High-throughput imprinted non-metal S-scheme heterojunction self-cleaning membrane with tight adhesion via dopamine for selective photodegradation of TC

The traditional photocatalysts have no selective photocatalysis ability and are difficult to separate and recycle. Herein, the imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (IM-NSH-PM) was prepared via imprinting modification technology and dopamine (DA) tight adhesion method, which possessed high throughput (2548.6 L m−2 h−1 bar−1), good self-cleaning performance, excellent stability and recovery performance. The cross-linking and polymerization of DA on PVDF membrane surface can form a strong interaction between basement membrane and imprinted modified non-metal S-scheme heterojunction (IM-NSH), which made IM-NSH-PM adhered closely together. Besides, the formed S-scheme heterojunction between PDI and g-C3N4, which weakened the recombination rate of electrons and holes and further improved the photodegradation ability. The photodegradation rate of TC by IM-NSH-PM reached 71.88%. More importantly, under the action of imprinting modification, IM-NSH was endowed with many imprinted cavities consistent with the three-dimensional structure of tetracycline (TC), thereby TC can be preferentially selective adsorbed and degraded, and the selectivity coefficient of IM-NSH-PM to non-imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (NIM-NSH-PM) was 1.88. This work shows a meaningful idea for exploring self-cleaning membranes with good selective photodegradation ability for the target pollutant.

NMP-induced surface self-corrosion-assisted rapid spin-coating method for synthesizing imprinted heterojunction photocatalyst anchored membrane towards high-efficiency selective degradation tetracycline

The membrane immobilization of imprinted photocatalysts is a good cooperative model, which not only gives self-cleaning and selectivity to the membrane but also solves the problem of difficult recycling and reuse of powder catalysts. Nevertheless, the problem of catalyst encapsulation and pore blockage limits its practical application. Herein, 1-methyl-2-pyrrolidone (NMP)-induced surface self-corrosion-assisted rapid spin-coating method was first proposed to prepare imprinted perylene diimide/poly-3,4-ethylenedioxythiophene heterojunction photocatalyst anchored membrane (I-PDI/PEDOT-M) with high stability and permeability. NMP can corrode polyvinylidene fluoride (PVDF) membrane and cause pore wall collapse on PVDF surface. The collapse of the pore wall firmly anchored the imprinted PDI/PEDOT heterojunction photocatalyst (I-PDI/PEDOT) into the surface pore of the PVDF membrane, effectively enhancing the stability. More importantly, this method did not produce a dense layer of traditional spin-coating solution, and I-PDI/PEDOT was fully exposed in the surface pores of the membrane to contact pollutants, thus maintaining high water flux and photodegradation activity. Besides, the construction of heterojunction structure and the introduction of imprinted cavities resulted in the good self-cleaning performance, excellent photocatalytic performance and significant specific degradation ability of I-PDI/PEDOT-M. The degradation activity of tetracycline (TC) with I-PDI/PEDOT-M was 11.05 times that of ciprofloxacin, and the selectivity coefficients of I-PDI/PEDOT-M were 2.51and 1.63 relative to PDI-M and non-imprinted PDI/PEDOT heterojunction photocatalyst, respectively. Additionally, the theoretical calculation and toxicity experiment proved that the toxicity was significantly reduced after degrading TC by I-PDI/PEDOT-M. This work provides an interesting idea for the design of highly stable and permeable photocatalytic membrane and highly selective degradation of specific pollutant.

Preparation of a Superhydrophobic Surface by a One-Step Powder Pressing Method with Liquid Silicone Rubber As the Carrier.

The preparation methods of the superhydrophobic surface play an important role in its application, but most of the existing preparation methods are complicated in operation, high in cost, and polluting to the environment. In order to find a simple, rapid, low-cost, and nonenvironmentally polluting preparation method of the superhydrophobic surface, this paper used liquid silicone rubber as the carrier. Before the liquid silicone rubber was nearly cured, it was evenly covered with a layer of silicon dioxide powder, and then 5 N weight was used to compact the powder on the rubber surface, so that the superhydrophobic surface was quickly formed on its surface. The wettability, bouncing performance, self-cleaning performance, and bending durability of liquid silicone rubber before and after treatment were compared. The results show that the static contact angle and rolling angle of the liquid silicone rubber after powder pressing were 158.22 ± 2.01° and 1.00 ± 0.50°, respectively. Moreover, the superhydrophobic surface formed by the powder pressing method had good self-cleaning performance, high temperature resistance, bending resistance, and excellent droplet bounce performance. The strategy of preparing a superhydrophobic surface by a one-step powder pressing method may be applied to the preparation of the superhydrophobic surface on a large scale.

Multifunctional Integrated Superhydrophobic Coatings with Unique Fluorescence and Micro/Micro/Nano-Hierarchical Structures Enabled by In Situ Self-Assembly

Conferring versatility to superhydrophobic materials is extremely desirable to advance their utility. Herein, we have developed a superhydrophobic material with montmorillonite as microskeleton supports and in situ grown ZIF-8 nanoparticles and loaded them with newly developed fluorescent carbon dots. In situ growth of the ZIF-8 on OMMT constructs a dense nanoscale rough structure and meanwhile self-assembly generates abundant microporous, thus forming unique hierarchical microporous/microsheet/nanoparticle tri-tier micro and nano structures. Then the multifunctional superhydrophobic coating is fabricated by a facile spraying technique using polydimethylsiloxane (PDMS) as a multifunctional polymer binder. The PDMS/RB-CDs/ZIF-8@OMMT exhibits superhydrophobicity with a water contact angle of 164.7° and a water sliding angle of 1.4°, which also possesses good self-cleaning performance. Moreover, novel carbon dots are developed in this work which can confer unique fluorescent properties and photothermal properties to materials. Fluorescence characterization reveals the multiple emission peaks among 300-800 nm and excitation wavelength dependence and independence. Photothermal experiments unveil an efficient light-to-heat conversion caused by the light traps and absorption wavelengths associated with photothermal heating. Benefiting from the dense microporous/microsheet/nanoparticle structures, the superhydrophobicity is still maintained after 120 cycles of abrasion. Moreover, electrochemical impedance spectroscopy (EIS) reveals a significant increase in impedance, which is associated with excellent corrosion resistance. The superhydrophobic coating also exhibits superior UV resistance and good thermal stability. Multifunctional fluorescent superhydrophobic materials will enable the development of various and potential applications in different fields.

Application of Superhydrophobic Mesh Coated by PDMS/TiO2 Nanocomposites for Oil/Water Separation.

Superhydrophobic materials have recently attracted great interest from both academia and industry due to their promising applications in self-cleaning, oil-water separation, etc. Here, we developed a facile method to prepare hybrid PDMS/TiO2 fiber for superhydrophobic coatings. TiO2 could be uniformly distributed into PDMS, forming a hierarchical micro/nano structure on the surface of the substrate. The contact angle of the superhydrophobic coating could reach as high as 155°. The superhydrophobic coating possessed good self-cleaning performance, corrosion resistance, and durability. It was found that gravity-driven oil-water separation was achieved using stainless steel mesh coated with the PDMS/TiO2 coating. More importantly, the coated filter paper could not only separate oil and pure water but also corrosive solutions, including the salt, acid, and alkali solution.

Simultaneous degradation and separation of antibiotics in sewage effluent by photocatalytic nanofiltration membrane in a continuous dynamic process

Bifunctional photocatalytic nanofiltration (PNF) membrane is increasingly concerned in practical micro-polluted water purification, but there are still several bottlenecks that inhibit its practicality. In this context, the feasibility of a novel metal-free and visible light-responsive surface-anchored PNF membrane for simultaneously removing target antibiotics in real sewage effluent in a continuous dynamic process was explored. The results showed that the optimal PNF-4 membrane was expectedly consisted of an inside tight sub-nanopore structured separation layer and an outside thinner, smoother, super hydrophilic mesoporous degradation layer, respectively. Consequently, the activated PNF-4 membrane could synergistically reduce trimethoprim and sulfamethoxazole concentrations to below two orders of magnitude, accompanying with almost constant high water permeability, suggesting that the hydrophilic modification of the mesoporous degradation layer basically offsets its inherent hydraulic resistance. Also, after repeating the fouling-physical rinsing process three times lasted for 78 h, only sporadic adherent contaminants remained onto the top surface, together with the minimal total and irreversible fouling ratios (as low as 7.2% and 1.2%, respectively), strongly demonstrated that PNF-4 membrane displayed good self-cleaning performance. Undoubtedly, this will significantly reduce its potential cleaning frequency and maintenance cost in long-term operation. Meanwhile, the acute and chronic biotoxicities of its permeate to Virbrio qinghaiensis sp. -67 were also reduced sharply to 2.22% and 0.45%, respectively. All of these evidences suggest that the dual functions of PNF-4 membrane are synergetic in an uninterrupted permeating process. It will provide useful insights for continuously enhancing the practicality and effectiveness of PNF membrane in actual micro-polluted water purification scenarios.

Fabrication of C6-Fluorocarbon-dendrimer-based superhydrophobic cotton fabrics for multifunctional aspects

C6-Fluorocarbon-dendrimer has been applied to the cotton knit fabric to develop oil–water repellent, oil–water separation, acid-resistant, self-cleaning, UV-resistant, and antibacterial properties. The C6-Fluorocarbon (FC)-dendrimer-coated 100% cotton single jersey knitted fabric samples were prepared using the “pad-dry-cure” method. The 90 g/L and 100 g/L FC-dendrimer-treated cotton fabrics showed excellent water repellency and oil–water separation as well as good self-cleaning performance. However, air permeability and heat conductivity were reduced by 13%, 15%, and 40%, 54%, for 90 g/L and 100 g/L FC-dendrimer-treated cotton fabrics compared to untreated fabrics. The presence of FC-dendrimer in the treated fabric was confirmed by FTIR, SEM, EDX, and XRD analyses. SEM analysis was employed to study the morphology of deposited FC-dendrimer particles on the fabric surface. TGA and DTA evaluated thermal performance. The FC-dendrimer-treated fabric also showed acid resistance, self-cleaning performance, and UV resistance attribute. In addition, Bacterial population growth appears to be less in the FC-dendrimer-treated sample than in the untreated sample. Overall, the result suggests that FC-dendrimer can be a valuable ingredient in the manufacture of multifunctional products.

Fabrication of Ultrahydrophobic Epoxy Coating Modified by SiO2-PDMS for Corrosion Protection and Self-Cleaning

In this work, ordinary epoxy coatings were modified by hydrophobic nanoSiO2 and hydroxyl PDMS to construct ultrahydrophobic epoxy coatings for corrosion protection and self-cleaning of phosphatized Q235 carbon steel. Ordinary epoxy polymer coating was fabricated via polyaddition reaction between E44 (bisphenol A epoxy resin oligomer) and DDM (4,4-diaminodiphenyl methane). The microscopic morphologies of coatings showed that many SiO2 nanoparticles were presented on the surface of ultrahydrophobic epoxy coating. Through static water contact angle measurement, the modified epoxy coating displayed ultrahydrophobicity with a water contact angle of approximately 150°. However, adding too much nanoSiO2 caused cracks on the modified epoxy coating, which deteriorated the corrosion resistance of the coating. According to the corrosion test results, the modified coating added with 6.7 wt% hydrophobic nanoSiO2 and chemically modified with hydroxyl PDMS showed the best corrosion protection performance, which was reflected by the high impedance of approximately 109 Ω·cm2 after 50 d immersion in 3.5 wt% NaCl (aq.). Besides, the coating also presented good self-cleaning performance. The coating extracted from the slurry still remained clean without any contamination.

Superhydrophobic Polyurethane Membrane with a Biomimetically Hierarchical Structure for Self-Cleaning.

In this study, a stable and durable hexadecyltrimethoxysilane (HDTMS)/thermoplastic polyurethane (TPU) superhydrophobic film is successfully prepared by a simple and low-cost two-step method, namely, carrying out biomimetically hierarchical structures and low surface energy material modification concurrently. Meanwhile, effective parameters affecting the water contact angle (WCA) are studied and optimized. More importantly, under optimum parameters, the maximum WCA is 165°, the minimum slide angle (SA) is 3°, and the adhesion force is 13 μN, showing good self-cleaning performance. Besides, considerable mechanical stability to withstand 4000 tension or 5000 compression cycles, breathability, and moisture penetrability, as well as chemical resistance with sustained superhydrophobic properties in various harsh environments, are presented.

Integration of in situ Fenton-like self-cleaning and photothermal membrane distillation for wastewater treatment via Co-MoS2/CNT catalytic membrane

Intensive energy dependence and membrane fouling are the inherent limitations of membrane distillation (MD) process for the application. Solar energy is promising sustainable energy for both alleviating the energy shortage and activating the Fenton-like reaction for various pollutants degradation. By in situ integrating Fenton-like and photothermal MD processes, the restriction of energy dependence and membrane fouling on the MD process might be effectively liberated. In this study, Co-MoS2/CNT was introduced to PTFE membrane modification through vacuum filtration, which simultaneously endowed the membrane with optothermal effect and Fenton-like activation abilities. The membrane was evaluated in a dye wastewater treatment under the irradiation of 1 kW/m2 light density. Results showed that the degradation degree of RhB can reach 80 % within 1 h on the feed side, while the permeate flux maintains at 2.43 kg/(m2·h) with an initial feed temperature of 35 °C. In addition, the flux of the Co-MoS2/CNT/PTFE membrane can be maintained above 95 % after three fouling-cleaning cycles, indicating that the modified membrane has a good self-cleaning performance. This work provides a low carbon option which improving mass transfer effect and fouling control ability for dye wastewater treatment by MD using solar energy.