Gang Wang

A new SPA based on lipoic acid and hydroxypropyl β-cyclodextrin that has tailored adhesion behavior and unique time-temperature dependent characteristics for on-demand adhesion controlled via a simple cyclic heating–cooling strategy is presented.

Hydrophilic and underwater superoleophobic membranes can handle membrane pollution from low-viscous oils in oily wastewater, but application in high-viscous oils and other foulants is limited. In this study, a filtration membrane with outstanding anti-fouling performances in complicated wastewater purification is designed and developed, which not only prevents oils from the membrane bulk because of the underwater superoleophobicity but also activates peroxymonosulfate advanced oxidation processes (PMS-AOPs) generating reactive species for the degradation of various pollutants on the membrane. Briefly, amorphous Fe-based metal–organic frameworks (aMOF) were covered on the polyvinylidene difluoride/polyacrylic acid (PVDF/PAA) blend membrane and further modified by amorphous Co(OH)₂ nanosheets, therefore an amorphous Fe/Co synergistic catalyst-modified membrane (M-aMOF-Co) was engineered for the first time. Compared with the membrane modified by crystalline MOF (M-cMOF) and the membrane decorated by amorphous Co(OH)₂ nanosheets (M-Co), M-aMOF-Co exhibits more stability and greater PMS-AOP performances against dyes and antibiotics (such as methylene blue, rhodamine B, tetracycline, levofloxacin, and enrofloxacin), due to the fast redox reaction between Co²⁺ and Fe³⁺ on the amorphous catalysts. For the separation of a soybean oil-in-water emulsion containing rhodamine B and tetracycline, M-aMOF-Co has a high flux recovery rate (FRR_P) of 98.1% and low pollution resistance (R_fp) of 0.1 × 10¹¹ m⁻¹, which are superior to M-cMOF (86.8% and 0.6 × 10¹¹ m⁻¹) and pure PVDF/PAA membrane without modification (called M, 21.0% and 7.1 × 10¹¹ m⁻¹). This study not only pioneers a novel application of amorphous Fe/Co catalysts in PMS-AOPs but also offers an innovative solution for membrane fouling in wastewater reclamation.

Superhydrophilic surfaces have attracted great interest in antifogging applications. However, balancing long-lasting superhydrophilicity and high transparency on antifogging surfaces remains a serious problem to be solved. The objective of this work is to prepare superhydrophilic coatings with transparent and long-lasting antifogging properties. In the design, a three-step method was used to obtain the target coatings: (1) magnetron sputtering deposition of a TiN film to provide high intensity, (2) anodic oxidation of the TiN film to obtain TiO₂ nanoparticles intended for nanostructured antireflective and capillary structures, and (3) the sol-gel method for the preparation of Fe³⁺-doped TiO₂ coatings using spin-coating in order to achieve superhydrophilicity. The nanostructures, due to their subwavelength dimensions, not only provide high transparency but also recoverable superhydrophilicity owing to the presence of a capillary anchoring effect that prevents the coating from dissolving and peeling off after soaking. The doping of Fe³⁺ broadened the photoresponse range and maintained the long-lasting superhydrophilicity. Tests showed that the 2 mol % Fe³⁺-doped TiO₂ coating with nanostructures exhibited the highest transparency, longest-lasting superhydrophilicity, and antifogging properties. Furthermore, the coating provided excellent self-cleaning properties, as well as mechanical and chemical stability.

This review highlights advancements in the thermal management of graphene-based polymer composites, emphasizing material selection, preparation, modification, structural design, and innovative applications.

Superspreading surfaces with excellent water transport efficiency are highly desirable for addressing thermal failures through the liquid–vapor phase change of water in electronics thermal management applications. However, the trade‐off between capillary pressure and viscous resistance in traditional superspreading surfaces with micro/ nanostructures poses a longstanding challenge in the development of superspreading surfaces with high cooling efficiency in confined spaces. Herein, a heat‐treated hierarchical porous enhanced superspreading surface (HTHP) for highly efficient electronic cooling is proposed. Compared with the single porous structures in nanograss, nanosheets, and copper foam, HTHP with hierarchical honeycomb pores effectively resolves the trade‐off effect by introducing large vertical through‐pores to reduce viscous resistance, and connected small pores to provide sufficient capillary pressure synergistically. HTHP exhibits excellent capillary performance in both horizontal spreading and vertical rising. Despite a thickness of only 0.33 mm, the as‐prepared ultrathin vapor chamber (UTVC) fabricated to exploit the superior capillary performance of HTHP achieved effective heat dissipation with outstanding thermal conductivity (12 121 Wm⁻¹K⁻¹), and low thermal resistance (0.1 KW⁻¹) at a power of 5 W. This regulation strategy based on hierarchical honeycomb porous structures is expected to promote the development of high‐performance superspreading surfaces with a wide range of applications in thermal management.

Hydrogels with wet adhesion are promising interfacial adhesive materials; however, their adhesion in water, oil, or organic solvents remains a major challenge. To address this, a pressure-sensitive P(AAm-co-C₁₈ )/PTA-Fe hydrogel is fabricated, which exhibits robust adhesion to various substrates in both aqueous solutions and oil environments. It is demonstrated that the key to wet adhesion under liquid conditions is the removal of the interfacial liquid, which can be achieved through rational molecular composition regulation. By complexing with hydrophilic polymer networks, phosphotungstic acid (PTA) is introduced into the hydrogel network as a physical cross-linker and anchor point to improve the cohesion strength and drive the migration of polymer chains. The migration and rearrangement of hydrophilic and hydrophobic polymer chains on the hydrogel surface are induced by the electrostatic interactions of Fe³⁺ , which create a surface with interfacial water- and oil-removing properties. By co-regulating the hydrophilic and hydrophobic polymer chains, the P(AAm-co-C₁₈ )/PTA-Fe hydrogel is able to act as a pressure-sensitive adhesive under water and oils with adhesion strength of 92.6 and 90.0 kPa, respectively. It is anticipated that this regulation strategy for polymer chains will promote the development of wet adhesion hydrogels, which can have a wide range of applications.

Lipoteichoic acid (LTA) is a major structural and functional molecule in the Gram-positive bacteria membrane. Knowledge of LTA adsorption at interfaces and its solution self-assembly is crucial to understanding its role in bacterial adhesion and colonisation, infections and inflammations. Here, we report the self-assembly behaviour of LTA extracted from Bacillus subtilis, a Gram-positive bacterium, in an aqueous solution using cryogenic transmission electron microscopy (Cryo-TEM) and small-angle neutron scattering (SANS) and its adsorption behaviour at the solid–liquid interface using atomic force microscopy (AFM) imaging and quartz crystal microbalance with dissipation monitoring (QCM-D). The Cryo-TEM results indicated the formation of spherical LTA micelles that decreased in size on addition of calcium chloride (CaCl₂), attributed to charge neutralisation and possible formation of stable Ca²⁺-bridges between the phosphate groups on neighbouring LTA chains. Analysis of the SANS data from the polydisperse LTA aggregates in solution using the two Lorentzian model revealed the existence of two correlation lengths, which could respectively account for the presence of LTA micelle clusters and the local structure arising from LTA intra-molecular interactions. In the presence of CaCl₂, the decrease in the correlation lengths of the clusters indicated possible disruption of H-bonding by Ca²⁺, leading to poorer water-LTA interactions. At higher temperatures, the correlation length corresponding to the clusters increased, indicating a temperature assisted growth caused by the fluidization of micellar core and dehydration of the polar LTA chains. AFM imaging showed that adsorption of LTA aggregates at the SiO₂–water interface was significantly prompted by the addition of CaCl₂, also confirmed by QCM-D measurements. These unprecedented nanoscopic structural details on the morphology of LTA aggregates in solution and at the solid–liquid interface add to our fundamental understanding of its self-assembly behaviour hitherto underexplored.

A photocatalytic membrane with significant degradation and antifouling performance has become an important part in wastewater treatment. However, the low catalyst loading on the polymer membrane limits its performance improvement. Herein, we fabricated poly(vinylidene fluoride) (PVDF) and poly(acrylic acid) (PAA) blend membranes with a rough surface via a vapor-induced phase separation (VIPS) process. Then Fe³⁺ was cross-linked with the carboxyl groups on the membrane surface and further in situ mineralized into β-FeOOH nanorods. The resultant membranes exhibit not only hydrophilicity and underwater superoleophobicity but also favorable separation efficiency and high water flux in oil-in-water emulsions separation. Under visible light irradiation, the membrane can degrade methylene blue (MB) to 95.2% in 180 min. More importantly, the membrane has a significant photocatalytic self-cleaning ability for crude oil with a flux recovery ratio (FRR) as high as 94.1%. This work brings a new strategy to fabricate the rough and porous surface for high loading of the hydrophilic photo-Fenton catalyst, improving the oil/water emulsion separation and antifouling performance of the membranes.