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Thrombosis and infection are two major complications associated with central venous catheters (CVCs), which significantly contribute to morbidity and mortality. Antifouling coating strategies currently represent an efficient approach for addressing such complications. However, existing antifouling coatings have limitations in terms of both duration and effectiveness. Herein, we propose a durable zwitterionic polymer armor for catheters. This armor is realized by pre-coating with a robust phenol-polyamine film inspired by insect sclerotization, followed by grafting of poly-2-methacryloyloxyethyl phosphorylcholine (pMPC) via in-situ radical polymerization. The resulting pMPC coating armor exhibits super-hydrophilicity, thereby forming a highly hydrated shell that effectively prevents bacterial adhesion and inhibits the adsorption and activation of fibrinogen and platelets in vitro. In practical applications, the armored catheters significantly reduced inflammation and prevented biofilm formation in a rat subcutaneous infection model, as well as inhibited thrombus formation in a rabbit jugular vein model. Overall, our robust zwitterionic polymer coating presents a promising solution for reducing infections and thrombosis associated with vascular catheters.

Proteins, cells and bacteria adhering to the surface of medical devices can lead to thrombosis and infection, resulting in significant clinical mortality. Here, we report a zwitterionic polymers-armored amyloid-like protein surface engineering strategy we called as “armored-tank” strategy for dual functionalization of medical devices. The “armored-tank” strategy is realized by decoration of partially conformational transformed LZM (PCTL) assembly through oxidant-mediated process, followed by armoring with super-hydrophilic poly-2-methacryloyloxyethyl phosphorylcholine (pMPC). The outer armor of the “armored-tank” shows potent and durable zone defense against fibrinogen, platelet and bacteria adhesion, leading to long-term antithrombogenic properties over 14 days in vivo without anticoagulation. Additionally, the “fired” PCTL from “armored-tank” actively and effectively kills both Gram-positive and Gram-negative bacterial over 30 days as a supplement to the lacking bactericidal functions of passive outer armor. Overall, this “armored-tank” surface engineering strategy serves as a promising solution for preventing biofouling and thrombotic occlusion of medical devices.

Hydrogels have obtained extensive attention in oil–water separation due to their high hydrophilicity and weak viscosity. However, most hydrogels have limited applications due to their subpar mechanical qualities. The interpenetrating network gives the hydrogel material high mechanical properties due to the presence of physical and chemical crosslinking. Hence, polyvinyl alcohol/chitosan/polyacrylamide interpenetrating polymer network hydrogel (HAPC‐Gel) was created in this study. HAPC‐Gel coating filter cloth showed underwater super‐oleophobic (the oil contact angles about 159°) and could stably separate oil–water mixtures in different oil phases and complex environments (acids, bases, salts), and the removal rate is still above 99% after 20 cycles of separation. Furthermore, the water could be divided from the oil‐in‐water emulsion. These results indicate that HAPC‐Gel composites have promising applications in oil–water separation. [ABSTRACT FROM AUTHOR]

• Mg-doped anatase TiO 2 is made via solvothermal method without surfactant/template. • Mg-doped anatase TiO 2 shows good photocatalytic properties in visible light. • Mg-doped anatase TiO 2 endows ceramic glaze super-hydrophilicity (around 7°). • Mg-doped anatase TiO 2 endows ceramic glaze practical applications toward the use of sunlight. Self-cleaning materials have attracted considerable attention for their unique properties and practical applications in energy and environmental areas. Various commercial ceramic products developed based on photo-induced hydrophilic conversion of TiO 2 surfaces have also been provided. However, UV light induced and metastable character of anatase TiO 2 in medium/high temperature ceramic glaze limited practical applications for self-cleaning photocatalytic materials, which needs further development to improve their efficiency and utilities. In this work, Mg-doped anatase TiO 2 was synthesized via a template-free and surfactant-free solvothermal method. The results indicated that MgCl 2 ·6H 2 O content played key roles in the formation of anatase TiO 2. Compared to TiO 2 -undoped sample, Mg-doped TiO 2 sample showed higher photodegradation rate of 99.5 % in 80 min exposed to visible light irradiation. Owing to the introduction of the catalyst, the ceramic glaze showed super-hydrophilicity (water contact angle around 7°) and exhibited excellent stain resistance (e. g. the dried Marker ink on the glaze can immediately float once meeting water after 10 cycles). The glaze after more times recycles could restore super-hydrophilicity is irradiated by visible light for 1 h. This indicates that the introduction of Mg-doped anatase TiO 2 demonstrated great practical applications for self-cleaning ceramics toward sunlight. [ABSTRACT FROM AUTHOR]

Cation–π interaction is one of the most important noncovalent interactions found in biosystems, which has attracted great interests for the engineering of functional materials. In this work, one‐step assembly of super‐hydrophilic coatings via surface modification with polyphenols and cations is reported based on cation–π interactions. Hydrophilicity of surface coatings is tunable by the variation of cations based on the different affinity between polyphenols and cations. Copper meshes coated with tannic acid and tetramethylammonium demonstrate super‐hydrophilicity and high stability due to the strong cation–π interaction between catechol/pyrogallol and cations. The super‐hydrophilic coatings show high oil breakthrough pressure, self‐cleaning, and anti‐fogging properties, which can efficiently separate the mixture of oil and water. This study provides an avenue to explore the cation–π interactions for super‐hydrophilic coatings. [ABSTRACT FROM AUTHOR]

Developing cost‐effective, highly active, and robust electrocatalysts for oxygen evolution reaction (OER) at high current density is a critical challenge in water electrolysis since the sluggish kinetics of the OER significantly impedes the energy conversion efficiency of overall water splitting. Here, a 1D nanothorn‐like Nb−CoSe2/CC (CC=carbon cloth) structure was developed as an efficient OER catalyst. The optimized Nb−CoSe2/CC catalyst exhibited remarkable OER performance with the low overpotentials of 220 mV at 10 mA cm−2 and 297 mV 200 mA cm−2 and a small Tafel slope (54.1 mV dec−1) in 1.0 m KOH electrolyte. More importantly, the Nb−CoSe2/CC electrode displayed superior stability after 60 h of continuous operation. In addition, cell voltages of 1.52 and 1.93 V were required to achieve 10 and 500 mA cm−2 for the electrolyzer made of Nb−CoSe2/CC (anode) and the Pt/C (cathode). Density functional theory (DFT) calculations combined with experimental results revealed that incorporating niobium into the CoSe2 could optimize the adsorption free energy of the reaction intermediates and enhance the conductivity to improve the catalytic activity further. Additionally, the super‐hydrophilicity of Nb−CoSe2/CC resulting from the surface defects increased the surface wettability and facilitated reaction kinetics. These results indicate that Nb−CoSe2/CC intrinsically enhances OER performance and possesses potential practical water electrolysis applications. [ABSTRACT FROM AUTHOR]

In this study, we have developed a self-cleaning transparent coating on a glass substrate by dip coating a TiO2 ̶ KH550 ̶ PEG mixed solution with super-hydrophilicity and good antifogging properties. The fabrication of the thin-film-coated glass is a one-step solution blending method that is performed by depositing only one layer of modified TiO2 nanoparticles at room temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine the structure and morphology of the nanoparticles and the thin-film-coated glass. The surface functional groups were investigated using Fourier-transform infrared spectroscopy (FT-IR), and the optical properties of the glass coating were measured using a UV/Vis spectrometer. The results revealed that the KH-500-modified TiO2 film coating was in an anatase crystalline form. The hydrophilicity of the coated and uncoated glass substrates was observed by measuring their water contact angle (WCA) using a contact angle instrument. The maximum transparency of the coated glass measured in the visible region (380–780 nm) was approximately 70%, and it possessed excellent super-hydrophilic properties (WCA ~0°) at an annealing temperature of 350 °C without further need of UV or plasma treatment. These results demonstrate the super-hydrophilic coated glass surface has potential for use in self-cleaning and anti-fogging applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A COP photocatalyst named PDIN-PyN+ was synthesized by incorporating quaternary ammonium groups. • The hydrophilicity and light absorption region of PDIN-PyN+ were improved. • PDIN-PyN+ exhibited excellent removal performance for BPA and 2,4-D under visible light irradiation. • The degradation mechanism was investigated and ·O 2 –, 1O 2 , h+ were confirmed as the ROS. Conjugated organic polymers (COPs) originating from porphyrin and perylene bisimide exhibit promising capacity as photocatalysts benefiting from their inherent semiconducting characteristics, but most of them suffer from the hydrophobic properties, which strongly hinder their surface reactions and photocatalytic performance. To solve this problem, the quaternary ammonium groups were introduced into the porous skeleton of a COP-based photocatalyst (PDIN-Py) through Friedel-Crafts alkylation & Menschutkin reactions to yield a super-hydrophilic COP, denoted as PDIN-PyN+. Apart from the hydrophilicity, such post-modification strategy also enhances the visible light utilization, boosts the photogenerated carriers transport and endows PDIN-PyN+ with more positive zeta potential (21.9 mV), thus enhancing the electrostatic interaction with target anionic model pollutants including bisphenol A (BPA) and 2,4-dichlorophenoxyacetic acid (2,4-D) and improving the photocatalytic degradation performance. The removal efficiency (η) of PDIN-PyN+ towards 2,4-D (150 ppm) and BPA (20 ppm) can reach >99 % within 30 min under the irradiation of visible light, and the PDIN-PyN+ also exhibits excellent reusability and withstands various environmental influencing factors, thereby it shows great potential in real-water treatment scenarios. [ABSTRACT FROM AUTHOR]

The artificial construction of nature‐mimic inorganic–organic heterostructures is an emerging technological interest for protective surface applications. Mimicking the spikiness of sea urchin spicules for their protective function, here, the synthesis of zinc oxide (ZnO) nanometer‐scale spicules grown from micrometer‐scale polylactic acid (PLA) beads and fibers as super‐hydrophilic and bactericidal surfaces is reported. The thermodynamic mechanism behind the interfacial assembly of pre‐entrapped ZnO nanoparticles right at the PLA–water interfaces above the glass transition temperature of PLA, allowing for the follow‐up growth of nano‐spicules on the PLA templates is uncovered. This sea urchin‐like topography of ZnO nano‐spicules induces super‐hydrophilicity while generating reactive oxygen species as well as allowing the stabbing action of nano‐spicules. All of the above help enhance the bactericidal activity against both gram‐positive and gram‐negative bacteria in an unprecedentedly effective way. The findings conceptualize a new strategy to spontaneously assemble nanoparticles at the polymer–liquid interfaces, enabling various heterostructures with topography‐induced functions. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effect of heat treatment on the surface properties of carbon cloth electrodes and on the power generation efficiencies of microbial fuel cells (MFCs) configured with the heat-treated carbon cloth electrodes. Water contact angle measurements show that the hydrophobic surfaces of the carbon cloth became super-hydrophilic after heat treatment at a temperature above 500 °C, making it suitable for bacterial propagation. X-ray photoelectron spectrometry revealed that the signal of the C-O functional group of the carbon cloth electrodes increased in intensity after heat treatment. The MFCs configured with heat-treated carbon cloth electrode exhibited high power density of 16.58 mW/m2, whereas that of the untreated MFCs was only 8.86 mW m2. Compared with chemical modifications, heat treatment does not use any environmentally unsound acidic or toxic solutions during modification and are promising for manufacturing large-scale MFC stacks. [ABSTRACT FROM AUTHOR]

The presence of heavy metals in freshwater is a severe problem humanity faces. Remedies with high removal efficiency of heavy metals from contaminated water are crucial. However, existing studies often neglect effluent quality per World Health Organization (WHO) standards. Also, the reported conditions are either unrealistic to the actual contamination levels or unsuitable for large-scale applications. Here, we report the fabrication of zwitterionic graphene oxide (GO) by incorporating a pH-responsive group (i.e., Lysine) using N, N′-diisopropylcarbodiimide (DIC) as a coupling agent. The modified GO-Lys was then coated on a commercially available 0.45-μm Nylon membrane and was tested for selective removal of toxic heavy metals from synthetic water and human blood plasma samples while allowing essential metal ions. Consequently, lead was the most retained toxic metal (i.e., 99.99% retention with effluent quality meeting WHO standards) among nickel, arsenic, cadmium, and mercury (i.e., between 50 to 80% retention). These composite membranes also displayed excellent fouling resistance and inhibited bacterial adhesion onto the membrane surface, while maintaining stable performance over a long time and critical transmembrane pressure conditions. This research marks a significant advancement in environmental technologies, providing an effective solution for selectively removing heavy metal pollutants, with a particular focus on lead detoxification applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The changes in the valence states of Fe and Co within the cocatalyst FeCo 2 O 4 facilitate the water oxidation reaction. • The MgO interlayer effectively inhibits the recombination of photogenerated carriers. • The reaction kinetics are enhanced by the super-hydrophilic nature of the photoanode surface. To address the issue of inefficient charge transfer efficiency at the semiconductor/cocatalyst interface, we engineered a BiVO 4 /MgO/FeCo 2 O 4 array, incorporating a MgO interlayer. This design aimed to enhance the performance of photoelectrochemical (PEC) water splitting on BiVO 4 and FeCo 2 O 4. The introduced interlayer efficiently hinders hole backflow, promoting unimpeded charge migration within the multi-hybrid structure. This, in turn, significantly reduces the recombination of electron-hole pairs. In addition, the BiVO 4 /MgO/FeCo 2 O 4 undergoes a low-temperature plasma treatment, resulting in super-hydrophilicity. This treatment enhances charge migration efficiency and fosters extensive contact between the electrolyte and electrode interfaces. Photoelectrochemical analysis demonstrates that H-BiVO 4 /MgO/FeCo 2 O 4 exhibits exceptional performance for the oxygen evolution reaction (OER), showcasing a photocurrent density of 4.3 mA·cm−2 at 1.23 V vs. RHE in 0.5 M Na 2 SO 4 under AM 1.5 G (100 mW·cm−2) illumination. Remarkably, this value is 5.2 times higher than that observed for BiVO 4. Furthermore, the maximum incident photon to current conversion efficiency (IPCE) reaches an impressive 61.7 %, surpassing that of BiVO 4 and BiVO 4 /FeCo 2 O 4 by approximately 5.1 and 1.7 times, respectively. Additionally, the charge separation efficiency of H-BiVO 4 /MgO/FeCo 2 O 4 achieves a notable 83.4 %, and the charge injection efficiency is substantially improved. This study advocates for a straightforward yet highly effective approach to mitigate interfacial electron-hole recombination. [ABSTRACT FROM AUTHOR]

In this study, we have developed a self-cleaning transparent coating on a glass substrate by dip coating a TiO2 ̶ KH550 ̶ PEG mixed solution with super-hydrophilicity and good antifogging properties. The fabrication of the thin-film-coated glass is a one-step solution blending method that is performed by depositing only one layer of modified TiO2 nanoparticles at room temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine the structure and morphology of the nanoparticles and the thin-film-coated glass. The surface functional groups were investigated using Fourier-transform infrared spectroscopy (FT-IR), and the optical properties of the glass coating were measured using a UV/Vis spectrometer. The results revealed that the KH-500-modified TiO2 film coating was in an anatase crystalline form. The hydrophilicity of the coated and uncoated glass substrates was observed by measuring their water contact angle (WCA) using a contact angle instrument. The maximum transparency of the coated glass measured in the visible region (380–780 nm) was approximately 70%, and it possessed excellent super-hydrophilic properties (WCA ~0°) at an annealing temperature of 350 °C without further need of UV or plasma treatment. These results demonstrate the super-hydrophilic coated glass surface has potential for use in self-cleaning and anti-fogging applications.

Thrombosis and infection are two major complications associated with central venous catheters (CVCs), which significantly contribute to morbidity and mortality. Antifouling coating strategies currently represent an efficient approach for addressing such complications. However, existing antifouling coatings have limitations in terms of both duration and effectiveness. Herein, we propose a durable zwitterionic polymer armor for catheters. This armor is realized by pre-coating with a robust phenol-polyamine film inspired by insect sclerotization, followed by grafting of poly-2-methacryloyloxyethyl phosphorylcholine (pMPC) via in-situ radical polymerization. The resulting pMPC coating armor exhibits super-hydrophilicity, thereby forming a highly hydrated shell that effectively prevents bacterial adhesion and inhibits the adsorption and activation of fibrinogen and platelets in vitro . In practical applications, the armored catheters significantly reduced inflammation and prevented biofilm formation in a rat subcutaneous infection model, as well as inhibited thrombus formation in a rabbit jugular vein model. Overall, our robust zwitterionic polymer coating presents a promising solution for reducing infections and thrombosis associated with vascular catheters., Competing Interests: Prof. Zhilu Yang is an editorial board member for Bioactive Materials and was not involved in the editorial review or the decision to publish this article. All authors declare that there are no competing interests., (© 2024 The Authors.)

Protein and cell adhesion on temporary intravascular devices can lead to thrombosis and tissue embedment, significantly increasing complications and device retrieval difficulties. Here, we propose an endothelial glycocalyx-inspired dynamic antifouling surface strategy for indwelling catheters and retrievable vascular filters to prevent thrombosis and suppress intimal embedment. This strategy is realized on the surfaces of substrates by the intensely dense grafting of hydrolyzable endothelial polysaccharide hyaluronic acid (HA), assisted by an amine-rich phenol-polyamine universal platform. The resultant super-hydrophilic surface exhibits potent antifouling property against proteins and cells. Additionally, the HA hydrolysis induces continuous degradation of the coating, enabling removal of inevitable biofouling on the surface. Moreover, the dense grafting of HA also ensures the medium-term effectiveness of this dynamic antifouling surface. The coated catheters maintain a superior anti-thrombosis capacity in ex vivo blood circulation after 30 days immersion. In the abdominal veins of rats, the coated implants show inhibitory effects on intimal embedment up to 2 months. Overall, we envision that this glycocalyx-inspired dynamic antifouling surface strategy could be a promising surface engineering technology for temporary intravascular devices. This study provides an endothelial glycocalyx-mimicking dynamic antifouling surface strategy for temporary intravascular devices. With the synergy of hydrated antifouling surface and durable dynamic interface, this strategy enhances the anti-thrombosis capacities of catheters and suppresses intimal embedment of retrievable vascular filters, representing a promising potential to advance the application of temporary intravascular devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Super-wettability Cu mesh(200PPI) was successfully fabricated by direct oxidation, liquid deposition and vapor deposition in order to expand its application ranges and enhance microstructure effect. The structure, morphology and wettability of Cu mesh were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction, contact angle instrument and high speed video, and the optimum preparation process of film layer was obtained. The copper mesh with a layer of knife-like flower film shows super-hydrophilic wettability on which the spread velocity of water is 3.5m/s; moreover, the super-hydrophilic mesh with hybrid structures can be switched into super-hydrophobic material (>150°) by liquid deposition and vapor deposition methods; the optimum fabrication conditions to achieve super-hydrophobic performance >150° are oxidation time of 15min, oxidation temperature of 96℃, liquid deposition time of 30min and the treat temperature of 180℃ for 20min. Meantime, hybrid gaps of knife-like flowers are considered as the main reason of the super-wettability of meshes.

Super-hydrophilicity is a desired but rarely reported surface finish of polymer materials, so the methods for achieving such a property represent a great scientific and technological challenge. The methods reported by various authors are reviewed and discussed in this paper. The super-hydrophilic surface finish has been reported for polymers functionalized with oxygen-rich surface functional groups and of rich morphology on the sub-micrometer scale. The oxygen concentration as probed by X-ray photoelectron spectroscopy should be above 30 atomic % and the roughness as determined by atomic force microscopy over a few nm, although most authors reported the roughness was close to 100 nm. A simple one-step oxygen plasma treatment assures for super-hydrophilicity of few polymers only, but the technology enables such a surface finish of almost any fluorine-free polymer providing a capacitively coupled oxygen plasma that enables deposition of minute quantities of inorganic material is applied. More complex methods include deposition of at least one coating, followed by surface activation with oxygen plasma. Fluorinated polymers require treatment with plasma rich in hydrogen to achieve the super-hydrophilic surface finish. The stability upon aging depends largely on the technique used for super-hydrophilization.

A highly transparent and super-hydrophilic double-layer anti-reflection coating was prepared by a simple and economical sol-gel method based on the glass substrate. The bottom and top layer were respectively made with SiO _2 –TiO _2 sol and SiO _2 –TiO _2 -PEG300 sol. The average transmittance of the substrate coated with the double-layer coating is increased by 7% up to 97.4% in the visible light band, and the peak transmittance reaches 99% at about 550 nm. In addition, double-layer anti-reflection coating shows a good super-hydrophilic self-cleaning performance, and the transmittance of the coating can be restored by simple washing with water. Furthermore, due to the existence of anatase TiO _2 , the composite coating can restore the super-hydrophilicity damaged by dust under UV light.

Proteins, cells and bacteria adhering to the surface of medical devices can lead to thrombosis and infection, resulting in significant clinical mortality. Here, we report a zwitterionic polymers-armored amyloid-like protein surface engineering strategy we called as "armored-tank" strategy for dual functionalization of medical devices. The "armored-tank" strategy is realized by decoration of partially conformational transformed LZM (PCTL) assembly through oxidant-mediated process, followed by armoring with super-hydrophilic poly-2-methacryloyloxyethyl phosphorylcholine (pMPC). The outer armor of the "armored-tank" shows potent and durable zone defense against fibrinogen, platelet and bacteria adhesion, leading to long-term antithrombogenic properties over 14 days in vivo without anticoagulation. Additionally, the "fired" PCTL from "armored-tank" actively and effectively kills both Gram-positive and Gram-negative bacterial over 30 days as a supplement to the lacking bactericidal functions of passive outer armor. Overall, this "armored-tank" surface engineering strategy serves as a promising solution for preventing biofouling and thrombotic occlusion of medical devices., Competing Interests: Prof. Zhilu Yang is an editorial board member for Bioactive Materials and was not involved in the editorial review or the decision to publish this article. All authors declare that there are no competing interests., (© 2023 The Authors.)

A facile method was used to create both of the super-hydrophilic and super-hydrophobic properties on polyester/cellulose fabric blend. The fabric was exposed to air corona discharge treatment without any extra chemical modification. The static contact angle of 0° and 167° was indicated for super-hydrophilic and super-hydrophobic samples, respectively. The decrease of intensity of active functional groups and the increase of roughness with a nano-scale pattern presented a super-hydrophobic surface that confirmed by ATR-FTIR, AFM and FESEM analysis. This is while the increase of intensity of the active functional groups and the surface roughness with a micro-scale pattern was shown for the super-hydrophilic sample. The wettability tests show the enhancement of hydrophobic and hydrophilic properties for 300 W–10 min and 800 W–10 min corona discharge treated samples, respectively. Therefore, there is a critical point of the corona discharge process that enables it to create hydrophobic and/or hydrophilic properties on the substrates. [ABSTRACT FROM AUTHOR]

A novel strategy for the synthesis of tungsten trioxide (WO 3 ) micro–nanostructures by thermal annealing of tungsten powder under ambient conditions is reported. The as–synthesized WO 3 samples are thoroughly characterized using powder X–ray diffraction, X–ray photoelectron spectroscopy, transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) measurement. The TEM results show that the size of highly crystalline WO 3 particles can be tuned from micro to nano by simply varying the annealing temperatures. The BET results demonstrate that the surface area and pore size of the synthesized WO 3 decreases with increasing annealing temperatures. Furthermore, the WO 3 synthesized at 550 °C (WO–550) exhibits not only higher surface area and pore size, but also excellent photocatalytic activity as well as super hydrophilicity compared to the other prepared and commercially available WO 3 . However, among the synthesized WO 3 particles, only WO–550 exhibits moderate electrochromic properties. Our strategy is facile, cheap, rapid, and highly reproducible for large–scale production, and the use of toxic precursors or additional capping agents is also eliminated. We believe that the synthesis of WO 3 by our method could have various practical industrial applications, and yield an excellent alternative to commercial WO 3 . [ABSTRACT FROM AUTHOR]

A facile and versatile approach for the preparation of super-hydrophilic, excellent antifouling and hemocompatibility membranes had been developed through the generation in situ of bio-inspired polydopamine (PDA) microspheres on PVDF membranes. SEM images showed that the PDA microspheres were uniformly dispersed on the upper surface and the lower surface of the modified membranes. And there were a great number of PDA microspheres immobilized on the cross-section, but the interconnected pores structure was not destroyed. These facts indicated the existence of membrane micro-reactor effect for the whole membrane structure. Considering the remarkable improvement of hydrophilicity, antifouling properties, and permeation fluxes, we also proposed the cluster phenolic hydroxyl effect for the PVDF/PDA hybrid membranes. And the cluster phenolic hydroxyl effect can be ascribed to the all directions distributed phenolic hydroxyl groups on the whole membrane structure. Besides, the self-driven filtration experiments showed the great wetting ability and permeability of the PVDF/PDA hybrid membranes in filtration process without any external pressure. This implied the existence of accelerating self-driven force after the water flow flowed into the internal of membranes, which contributed to the increase of water flow velocity. All the three aspects were in favor of the enhancement of hydrophilicity, antifouling properties and permeability of the modified membranes. Moreover, the conventional filtration tests, oil/water emulsion filtration tests and protein adsorption tests were also carried out to discuss the practical applications of PVDF/PDA hybrid membranes. And the hemocompatibility of the modified membranes was also proved to enhance greatly through the hemolysis tests and platelet adhesion tests, indicating that the membranes were greatly promising in biomedical applications. The strategy of material modification reported here is substrate-independent and can be extended to other substrate materials, and allows the development of novel functional membranes through secondary treatments. [ABSTRACT FROM AUTHOR]

Biomimetic specific surface structure could improve biological behaviors of specific cells and eventual tissue integration. Featuring titanium surface with structures resembling bone resorption lacunae (RL) can be a promising approach to improve the osteoblast responses and osseointegration of implants. As a most common used dental implant surface, sandblasting and acid etching (SLA) surface has micro-sized structures with dimensions similar to RL, but great differences exist when it comes to shape and contour. In this work, by anodizing titanium substrate in a novel HCOONa/CH 3 COONa electrolyte, RL-like crater structures were fabricated with highly similar size, shape and contour. Compared with SLA, it was much more similar to RL structure in shape and contour. Furthermore, through subsequent alkali-heat treatment, nano-sized structures that overlaid the whole surface were obtained, which further mimic undercuts features inside the RL. The as-prepared surface was consisted of crystalline titania and exhibited super-hydrophilicity with good stability. In vitro evaluation results showed that the surface could significantly improve adhesion, proliferation and differentiation of MG63 cells in comparison with SLA. This new method may be a promising candidate for biomimetic modification of titanium implant to promote osseointegration. [ABSTRACT FROM AUTHOR]

In this work, a manufacture of TiO 2 coatings doped with fluorine, in a concentration range of 0.6 to 6.7 at.%, is presented. The coatings were deposited onto silicon and quartz substrates with the help of radio frequency plasma enhanced chemical vapor deposition technique. They were characterized with regard to their elemental composition, chemical structure, phase composition, surface topography, optical properties, photo-wettability and bactericidal properties. For that purpose, such analytical techniques as X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy, atomic force microscopy, ultraviolet–visible absorption spectroscopy and variable angle spectroscopic ellipsometry were used. GIXRD analysis of the coatings doped with fluorine shows their amorphous structure. Apart from TiO 2 bonding, FTIR and XPS analyses of the films reveal a presence of Ti F and O F bonds. Surface morphology studies indicate an increasing number of surface defects along with growing fluorine content. The coatings exhibit promising optical properties with some of them showing a super-hydrophilic effect as well. On the other hand, the bactericidal effect of fluorine doped TiO 2 coatings is weaker than that of plain TiO 2 . [ABSTRACT FROM AUTHOR]

• This study investigated the influence of inclination angle and hydrophilicity of the surface on boiling. • CHF and boiling heat transfer coefficient increased by using the super-hydrophilic heater surface. • However, the enhancement reduced as the inclination angle increased. • Bubble dynamics on super-hydrophilic PCB heater were observed during the boiling experiment. This study investigated the boiling heat transfer characteristics of a super-hydrophilic surface with de-ionized water at different orientations. Pool boiling experiments were conducted at inclination angles of 45°, 90°, and 135° by rotating the experimental apparatus. The experimental results were analyzed to investigate the influence of inclination angle and hydrophilicity of the surface on the boiling heat transfer characteristics. Parameters such as the maximum and minimum vapor thicknesses, bubble wavelength, bubble velocity, BHTC (Boiling Heat Transfer Coefficient) and CHF (Critical Heat Flux) were measured during the experiment. An enhancement in the values of the parameters of the bubble dynamics was observed during the boiling experiment using the super-hydrophilic PCB (Printed Circuit Board) heater, indicating improved heat transfer during the experiment. The CHF of the super-hydrophilic PCB heater was enhanced by a maximum of 28% at an inclination angle of 45°; the enhancement reduced as the inclination angle increased. [ABSTRACT FROM AUTHOR]

Photo-induced super-hydrophilic thin films were fabricated on a quartz glass substrate by ultraviolet (UV) irradiation of a molecular precursor film at room temperature. A molecular precursor film exhibiting high solubility to both ethanol and water was obtained by spin-coating a solution involving a Ti(IV) complex; this complex was prepared by the reaction of Ti(IV) alkoxide with butylammonium hydrogen oxalate and hydrogen peroxide in ethanol. Transparent and well-adhered amorphous thin films of 160⁻170 nm thickness were obtained by weak UV irradiation (4 mW·cm−2 at 254 nm) of the precursor films for over 4 h at room temperature. The resultant thin films exhibiting low refractive indices of 1.78⁻1.79 were mechanically robust and water-insoluble. The chemical components of the thin films were examined by means of Fourier transform-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) spectra, focusing on the presence of the original ligands. The super-hydrophilic properties (evaluated based on the water contact angles on the surfaces) of the thin films after being kept in a dark condition overnight emerged when the aforementioned UV-light irradiation was performed for 10 min. It was additionally clarified that the super-hydrophilicity can be photo-induced repeatedly by UV irradiation for 10 min (indicated by a contact angle smaller than 4°) even after the hydrophilic level of the thin films had once been lowered by being in a dark condition for 4 h.

Water in the world is becoming an increasingly scarce commodity and the membrane technology is a most effective strategy to address this issue. However, the fouling and low flux of the polymeric membrane remains the big challenges. Novel modified Polyvinylidene fluoride (PVDF) membrane was introduced, in this work, using a novel treatment technique for an electrospun polymeric PVDF membrane to be used in oil/water separation systems. The Characterizations of the modified and pristine membranes showed distinct changes in the phase and crystal structure of the membrane material as well as the wettability. The modification process altered the surface morphology and structure of the membrane by forming hydrophilic microspheres on the membrane surface. Therefore, the proposed treatment converts the membrane from highly hydrophobic to be a superhydrophilic under-oil when wetted with water. Accordingly, in the separation of oil/water mixtures, the modified membrane can achieve an outstanding flux of 20664 L/m 2 . hr under gravity, which is higher than the pristine membrane by infinite times. Moreover, in the separation of the emulsion, a high flux of 2727 L/m 2 . h was achieved. The results exhibited that the modified membrane can treat a huge amount of oily water with a minimal energy consumption. The corresponding separation efficiencies of both of oil/water mixtures and emulsion are more than 99%. The achieved characteristics for the modified and pristine membranes could be exploited to design a novel continuous system for oil/water separation with an excellent efficiency. [ABSTRACT FROM AUTHOR]

Atmospheric dust on the surface of modern building glass requires frequent cleaning to keep high diaphaneity and esthetics. Visible light-induced super-hydrophilic anatase porous thin films with easy-to-clean and antifogging properties were controllably synthesized through the neutralization of ammonia and nitric acid-driven phase separation by sol-gel spin coating method. Surface microstructure, root-mean-squared roughness, crystalline structure, surface chemical composition, transmittance, hydrophilic, antifogging, and easy-to-clean properties of the films were characterized by super depth of field microscopy, atomic-force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible-near-infrared spectrophotometer and automatic contact angle measuring device, respectively. With NH·HO concentration increasing from 0.7 to 1.1 vol.%, the average pore size of anatase porous thin films increases from 1.05 to 2.36 μm and the water contact angles decrease from 5.2° to 1.7° under 100-lux visible light irradiation (400-800 nm). Besides, the larger NH·HO concentration, the larger root-mean-squared roughness roughness, ranging from 5.67 to 88.00 nm. Moreover, X-ray photoelectron spectroscopy results demonstrate that there are Ti-O bonds and Si-O bonds on the samples surface, indicating that porous area bottom is Si-O bonds by soda-lime glass. These films exhibit excellent visible light-induced super-hydrophilic, antifogging and easy-to-clean properties, which make them suitable to be used in modern buildings and automotive glass. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A super-hydrophilic coating with a macro/micro/nano triple hierarchical structure was prepared on titanium surface by a two-step micro-arc oxidation (MAO) treatment consisting of macropores (100–300 μm), microslots (3–10 μm) and submicro/nanopores (80–200 nm). The first hierarchical structures (macropores) were formed by MAO treatment in a NaNO 3 and NaOH electrolyte, and the latter two hierarchies, forming a “cortex-like” structure, were generated through a second MAO treatment in a Na 2 B 4 O 7 electrolyte. The influence of the concentration of NaOH in the electrolyte and MAO electrical parameters on the macroporous structure was explored. The morphology, composition, hydrophilicity and the formation of hydroxyapatite in simulated body fluid of the two types of structure, together with the combined structure, were studied. The results suggest that NaOH enhances the corrosion ability of NaNO 3 , and has a major effect on the size and uniformity of macropores. The coating hydrophilicity and the formation of hydroxyapatite of the coating were determined by the second step treatment, i.e. the “cortex-like” structure. This novel triple hierarchical structure may be promising to improve the adhesion of osteoblasts to implants as well as the fixation of implants. [ABSTRACT FROM AUTHOR]

• Synthesis of super-hydrophilic Ce3+-doped SiO 2 -TiO 2 nanocomposite by spin-coating. • The lowest bandgap of 2.85 eV and high transmittance of 87.7% in the visible light. • The water contact angle of 7.9° after exposure to blue light for 60 min. • Great potential for photocatalytic materials and protective films. Super-hydrophilic surfaces with slight water contact angles have a wide range of applications, especially for protective layers. Herein, high-purity 10-layer TiO 2 -SiO 2 :x%Ce3+ (x = 0 – 8) nanocomposite thin films (NCTFs) were fabricated by a facile spin-coating method. The X-ray diffraction, the Fourier transform-infrared spectroscopy, and Raman spectroscopy results confirmed the formation of the TiO 2 -SiO 2 NCTFs. X-ray photoelectron spectroscopy analysis strongly demonstrated the coexistence of Ce3+ and Ce4+ oxidation states on the surface of the NCTFs sample. The TiO 2 -SiO 2 :6%Ce3+ NCTFs exhibited the highest transmittance of 87.7% in the visible region and the lowest bandgap of 2.85 eV. Water contact angle results reveal that the NCTFs are super-hydrophilic under prolonged exposure to blue light (460 nm) irradiation. Our results demonstrate that the Ce3+-doped TiO 2 -SiO 2 NCTFs are to be used as a photovoltaic material, protective film for glasses, and other surfaces. [Display omitted] [ABSTRACT FROM AUTHOR]

The super-hydrophilic polymer coating film can easily be be peeled off from a substrate with the existence of water, which is a fatal drawback in practical applications. Herein, a facile approach is proposed to prepare UV-curable super-hydrophilic polyacrylate coating film that is chemically grafted on the surface of γ-methacryloxypropyltrimethoxysilane-modified glass substrate. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that the polyacrylate coating films were successfully grafted onto the glass substrate and exhibited rough micro-groove structure. The obtained polyacrylate coating film possessed super-hydrophilicity with the water contact angle close to nearly zero as well as good transmittance and antifogging property. [ABSTRACT FROM AUTHOR]

Water contact angles on three types of Si(1 1 1) and (0 0 1) surfaces were measured in nitrogen gas atmosphere without exposing them to air; the surfaces were prepared to be (I) cleaned and reconstructed, subsequently (II) atomic hydrogen (H) terminated, or (III) thinly oxidized in an ultrahigh vacuum (UHV) chamber. The surfaces were characterized by Auger electron spectroscopy and atomic force microscopy. The H-terminated Si surfaces showed as less hydrophilic with a water contact angle of about 37° on the (1 1 1) and about 60° on the (0 0 1) surface, respectively. The clean and oxidized surfaces showed as super-hydrophilic with the angles less than 6°. To quantitatively evaluate the contact angles on the super-hydrophilic surfaces, an optical interference fringe method was used under an optical microscope in air. The most super-hydrophilic surface was the oxidized Si(1 1 1) surface. The reactivity of the Si surfaces and their degree of hydroxyl group termination to the Si surfaces responsible for water wettability were discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiO2–SiO2 thin films confirm a natural and persistent super hydrophilicity. [•] These properties can be easily photo-regenerated after a long aging period. [•] The stability of the prewetting film is enhanced by an electrochemical double layer in conjunction with surface roughness. [•] The prewetting film is able to withstand to vaporization. [Copyright &y& Elsevier]

Developing cost-effective, highly active, and robust electrocatalysts for oxygen evolution reaction (OER) at high current density is a critical challenge in water electrolysis since the sluggish kinetics of the OER significantly impedes the energy conversion efficiency of overall water splitting. Here, a 1D nanothorn-like Nb-CoSe 2 /CC (CC=carbon cloth) structure was developed as an efficient OER catalyst. The optimized Nb-CoSe 2 /CC catalyst exhibited remarkable OER performance with the low overpotentials of 220 mV at 10 mA cm -2 and 297 mV 200 mA cm -2 and a small Tafel slope (54.1 mV dec -1 ) in 1.0 m KOH electrolyte. More importantly, the Nb-CoSe 2 /CC electrode displayed superior stability after 60 h of continuous operation. In addition, cell voltages of 1.52 and 1.93 V were required to achieve 10 and 500 mA cm -2 for the electrolyzer made of Nb-CoSe 2 /CC (anode) and the Pt/C (cathode). Density functional theory (DFT) calculations combined with experimental results revealed that incorporating niobium into the CoSe 2 could optimize the adsorption free energy of the reaction intermediates and enhance the conductivity to improve the catalytic activity further. Additionally, the super-hydrophilicity of Nb-CoSe 2 /CC resulting from the surface defects increased the surface wettability and facilitated reaction kinetics. These results indicate that Nb-CoSe 2 /CC intrinsically enhances OER performance and possesses potential practical water electrolysis applications., (© 2022 Wiley-VCH GmbH.)

Abstract: A surface with Ni micro–nano cones array (MCA) was fabricated with electro-deposition method and exhibited super-hydrophilic nature when freshly prepared. Spontaneous transition from super-hydrophilicity to super-hydrophobicity was observed when the surface was exposed in air at room temperature. The special surface structure of MCA played an important role in amplifying the surface wettability. Since the surface structure remained the same as the freshly prepared Ni MCA films during the storage, the transition was proved to be attributed to the change of surface chemical composition. Such wettability transition property of Ni MCA films might shed light on the high-tech areas of self-cleaners, anti-corrosion materials, anti-contamination materials, etc. [Copyright &y& Elsevier]

Abstract: A super-hydrophilic surface was prepared on the molybdenum substrate via a hydrothermal method. The scanning electron microscope (SEM) images show that many crystal grains with the size of about a hundred nanometers grown on the surface, which look like the seeds on the strawberry surface. The analysis by energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) proves that the seeds are MoO2 crystals. The results of wetting test reveal that the water contact angle is nearly 0° and the super-hydrophilicity can stably keep for more than 105 days. The mechanism of the super-hydrophilicity was discussed according to the Wenzel theory. [Copyright &y& Elsevier]

Abstract: Cr doped TiO2–SiO2 nanostructure thin film on glass substrates was prepared by a sol–gel dip coating process. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to characterize the structural and chemical properties of the films. A UV–vis spectrophotometer was used to measure the transmittance spectra of the thin film. The hydrophilicity of the thin film during irradiation and storage in a dark place was measured by a contact angle analyzer. The results indicated that Cr doping has a significant effect on the transmittance and super-hydrophilicity of TiO2–SiO2 thin film. [Copyright &y& Elsevier]

Abstract: Dendritic copper film with convertible extreme wettability is prepared on metal surface via electrodeposition. With field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and electrochemical measurement, the morphology, composition and formation mechanism of dendritic copper film were studied. It is found that the film is mainly composed of metallic copper. Also some residual cuprous oxide and chloride exist in the deposit. The single micron-sized dendrite consists of a main stem with side branches, on which the higher-order branches with the dimension of tens of nanometers grow. A hydrophobic modification can induce the conversion of the apparent wettability of film from super-hydrophilicity (with apparent water contact angle of 5±3°) to super-hydrophobicity (with apparent water contact angle of 154.1±3°), which is due to the capillary effect. The method proposed in this paper is time-saving and facile to operate, and it offers a promising technique to prepare metallic surface with a high wettability contrast for water. [Copyright &y& Elsevier]

rough TiO film was fabricated by sol-gel technique, the film exhibits perfect super-hydrophobicity with a contact angle of 150° and glide angle of about 5° after being modified with octyltrimethoxysilane. The super-hydrophobicity was converted to super-hydrophilicity by the irradiation of ultraviolet light for 20 h, the irradiated super-hydrophilic film evolves to be hydrophobic with a contact angle of about 120° on the condition of being placed in dark for 2 weeks. Finally the property of super-hydrophobicity of TiO film modified with octyltrimethoxysilane was discussed on the basis of Cassie's theory. [ABSTRACT FROM AUTHOR]

In this work, TiO and TiO-SiO thin films on glass substrates were prepared by the sol-gel dip coating process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to evaluate the structural and chemical properties of the films. The super-hydrophilicity was assessed by water contact angle measurement. XRD measurements confirmed the presence of polycrystalline anatase and rutile phases in the films. The water contact angle measurements showed that addition of SiO has a significant effect on the super-hydrophilicity of TiO thin films, especially if they are stored in a dark place. [ABSTRACT FROM AUTHOR]

Abstract: The cleanability of material surfaces is cause for concern for a lot of industrial and domestic applications. Here, we report on TiO2–SiO2 composite thin films deposited via a sol–gel route. These films exhibit a naturally persistent super-hydrophilicity and this property can easily be photo-regenerated after a long aging period in ambient atmosphere. Static and dynamic oil wettability experiments have been performed to assess the enhanced cleanability of such super-hydrophilic surfaces. This study shows how a suitable composite sol formulation enables the formation of films whose performances have practically no limitation on the long term, which allows envisaging applications for surfaces with enhanced cleanability in atmospheres where UV light cannot permanently be present. [ABSTRACT FROM AUTHOR]

In this paper, nanostructure TiO thin films were deposited on glass substrates by sol-gel dip coating technique. X-ray diffraction and Fourier transform infrared spectroscopy were used to determine film behaviour. The super-hydrophilicity was assessed by contact angle measurement. Photocatalytic properties of these films were evaluated by degradation of methylene blue under UV irradiation. The XRD pattern of TiO powder samples confirmed the presence of polycrystalline anatase phase with a crystal size of 17 nm. The results indicated that UV light irradiation had significant effect on super-hydrophilic and photocatalytic properties of TiO thin films. [ABSTRACT FROM AUTHOR]

Abstract: TiO2–SiO2 composite thin films have been deposited via a sol–gel route. Their morphological, physico-chemical, and wettability properties have been studied. It is shown that composite films exhibit an unexpected natural super-hydrophilicity that persists with time in the absence of any UV light exposure. Depending on the experimental conditions, this natural super-hydrophilicity can persist for at least eight weeks in ambient aging conditions. Such a property allows envisaging applications to surfaces with enhanced cleanability in atmospheres where UV light is not permanently present. It is shown that natural carbon contamination does not preponderantly influence the persistent super-hydrophilicity of TiO2–SiO2 composite films. This property is then studied and discussed with respect to the film morphological and physico-chemical properties. [Copyright &y& Elsevier]

Abstract: A biomimetic super-hydrophobic/super-hydrophilic micropatterned template was successfully fabricated by microwave plasma-enhanced chemical vapor deposition (MPECVD) and vacuum ultraviolet (VUV) lithography. Water drops were selectively condensed on super-hydrophilic regions of the template. In the solution of pH 2.6, carboxyl-terminated fluorescent polystyrene spheres were sedimented on super-hydrophobic regions due to electrostatic attractive forces between negative –COO− and positive –CH3 groups. Cu was also deposited densely on only super-hydrophobic regions through electroless plating. From these results, we revealed that the biomimetic super-hydrophobic/super-hydrophilic micropatterned template was used as site-selective chemical reaction field. [Copyright &y& Elsevier]

We have investigated a novel technique for the preparation of nano-sized Pt metals on Ti-containing mesoporous silica (TMS) thin film by photo-assisted deposition (PAD). The transparent TMS thin film was prepared on a quartz plate through sol–gel/spin coating. XRD, UV-Vis and Ti K-edge XAFS measurements revealed the formation of isolated Ti oxide species with a tetrahedral-coordination geometry in the silica framework. Deposition of Pt metal precursor on TMS thin film under UV-light irradiation, followed by reduction with molecular hydrogen, afforded a transparent thin film (Pt/TMS). The formation of highly dispersed nano-sized Pt metals having narrow size distributions was determined by Pd LIII-edge XANES and TEM analysis. The TMS and Pt/TMS thin films have been demonstrated to exhibit a strong hydrophilic property, even before UV irradiation, compared to the common mesoporous silica and TiO2 thin films. After UV-light irradiation, the contact angle of water droplet on the TMS and Pt/TMS thin films became extremely lower, indicating the appearance of the photo-induced super-hydrophilic property. [ABSTRACT FROM AUTHOR]

Abstract: A transparent and super-hydrophilic TiO2 film with high adhesion was prepared by simple self-assembly methods from aqueous solution at low temperature. The excellent adherence of TiO2 films was accomplished by introducing a buffer layer with sulfonate-modified surfaces and nanoasperity. Moreover, the structure and morphology of the films were successfully controlled by deposition temperature and the pH of precursor solution. By optimizing the several parameters of solution as well as the surface functionality of the substrate, the nano-structured TiO2 film with high adhesion showed a water contact angle of below 5° and the relative transmittance to slide glass of over 90%. The fabricated TiO2 film deposited under the optimized condition is not removed from substrate after several Scotch tape (STT) tests and immersing into several kinds of solvent. [Copyright &y& Elsevier]

Abstract: Previous studies suggest that granular interfaces induce a natural and persistent super-hydrophilicity in TiO2–SiO2 composite thin films deposited by sol–gel route. This effect enables to consider self-cleaning applications that do not require a permanent UV exposure, whereas such a permanent exposure is necessary for pure TiO2 films. In this study, TiO2–SiO2 composite thin films have been deposited from a TiO2 anatase crystalline suspension and different SiO2 polymeric sols. Wettability studies show that a suitable control of the TiO2–SiO2 mixed sol formulations noticeably enhances persistence of the natural super-hydrophilicity in composite films. It is shown that, beside granular interface effects, modifications in the composite film morphologies can noticeably influence wettability properties. [Copyright &y& Elsevier]