A novel high-durability oxidized poly (arylene sulfide sulfone) electrospun nanofibrous membrane for direct water-oil separation

Advances in photothermal regulation strategies: from efficient solar heating to daytime passive cooling

Photothermal regulation concerning solar harvesting and repelling has recently attracted significant interest due to the fast-growing research focus in the areas of solar heating for evaporation, photocatalysis, motion, and electricity generation, as well as passive cooling for cooling textiles and smart buildings. The parallel development of photothermal regulation strategies through both material and system designs has further improved the overall solar utilization efficiency for heating/cooling. In this review, we will review the latest progress in photothermal regulation, including solar heating and passive cooling, and their manipulating strategies. The underlying mechanisms and criteria of highly efficient photothermal regulation in terms of optical absorption/reflection, thermal conversion, transfer, and emission properties corresponding to the extensive catalog of nanostructured materials are discussed. The rational material and structural designs with spectral selectivity for improving the photothermal regulation performance are then highlighted. We finally present the recent significant developments of applications of photothermal regulation in clean energy and environmental areas and give a brief perspective on the current challenges and future development of controlled solar energy utilization.

New Strategy for Improvement of Interfacial Interactions between Poly(arylene sulfide sulfone) and Carbon Fiber by Grafting Polymeric Chains via Thiol-Ene Click Chemistry

A simple and efficient strategy for enhancing the interfacial interaction in carbon fiber-reinforced poly(arylene sulfide sulfone) (CF/PASS) composites by grafting polymeric chains via thiol-ene click chemistry is reported here. Simultaneously, three thiol compounds and carbon nanotubes were grafted on CFs to explore the reaction between the CF and thiol groups. X-ray photoelectron spectroscopy, Raman spectroscopy, and normalized temperature-dependent IR spectroscopy results confirm the successful grafting of three thiol compounds, carbon nanotubes, and polymer chains. Similarly, obvious changes on the CF surface can be seen before and after modification via scanning electron microscopy, such as grafted nanotubes and polymeric resin, and the increase in the modulus gradient and interfacial thickness of CF/PASS can be clearly seen via atomic force microscopy. All the results of micro and macro tests on mechanical properties indicate that connecting low molecular weight thiol-terminated PASS (HS-LPASS) onto CFs enhances the interfacial property and mechanical performance of CF/PASS to a greater extent. The interfacial shear strength, interlaminar shear strength, and tensile strength of CF@HS-LPASS-reinforced PASS (CF@HS-LPASS/PASS) increase significantly by 38.5, 43.6, and 24.4%, respectively. All the results demonstrate that thiol-ene click reactions can be used for CF modification; furthermore, in the presence of external stress, the grafted polymeric interphase can act as a "bridge layer" to improve the stress transfer efficiency.

Blending Electrostatic Spinning Fabrication of Superhydrophilic/Underwater Superoleophobic Polysulfonamide/Polyvinylpyrrolidone Nanofibrous Membranes for Efficient Oil-Water Emulsion Separation

The scarcity of water resources has led to widespread interest in the treatment of oily wastewater. This study prepared a novel superhydrophilic/underwater superoleophobic polysulfonamide (PSA)/polyvinylpyrrolidone (PVP) nanofibrous membrane through electrostatic spinning for efficient oil-water emulsion separation. The surface morphology, fiber diameter distribution, wettability properties, and oil-water emulsion separation performance of the membranes were investigated. Results showed that the addition of PVP increases the diameter of the fibers, which led to a loose, large, porous structure and improved the permeability of the membranes. A high pure-water flux of 2057 L·m^-2·h^-1 was obtained for membranes with PVP addition of 3 wt%, providing an 835% increase in pure-water flux compared with a pure PSA nanofibrous membrane (220 L·m^-2·h^-1). For n-hexane-in-water emulsions, the optimum membrane obtained a high separation efficiency of 99.7%, in which flux was 1.5 times greater than that of the pure PSA nanofibrous membrane. Moreover, the optimum membrane exhibited good recycling stability and solvent resistance. The as-prepared PSA/PVP nanofibrous membrane displayed high permeability, an outstanding rejection rate, resistance to organic solvents, and reusability for oil-water separation, providing great potential in practical membrane separation applications.

Multilevel structured PASS nanofiber filter with outstanding thermal stability and excellent mechanical property for high-efficiency particulate matter removal

Particulate matter (PM) pollution from industrialization poses a great threat to people's health. Although fiber-based filters are used effectively to capture PM, the traditional filters with large diameter suffer from low filtration efficiency, high pressure drop and low temperature resistance. In this study, multilayer poly arylene sulfide sulfone (M-PASS) composite filter was designed and fabricated via electrospinning technology. The M-PASS composite filter is sandwich-structure. Due to the unique structure and composition, the M-PASS filter exhibited outstanding removal efficiency of 99.97 ± 0.0050%, extremely low air resistance of 44.3 ± 0.7 Pa, excellent quality factor (QF) of 0.19 ± 0.0019 Pa^-1, and desirable mechanical strength of 7.0 ± 0.2 MPa. Furthermore, the as-prepared M-PASS filter can remain outstanding filtration performance at 200.0 ℃ due to the high thermal stability of PASS and the removal efficiency was still above 95.2 ± 0.4% after long-term filtration test. These results demonstrate that the structure of filter is the important one for air filtration and the M-PASS nanofiber filters have great potential in PM removal, especially under high temperature conditions.

High-performance filter membrane composed of oxidized Poly (arylene sulfide sulfone) nanofibers for the high-efficiency air filtration

In this study, a novel, oxidized poly (arylene sulfide sulfone) (O-PASS) nanofibrous membrane filter was successfully fabricated for the effective removal of particulate matter. PASS was electrospun into a nanofibrous membrane with an average nanofiber diameter of 0.31 µm and basis weight of 3 g/m². These specifications were chosen as they showed high particulate matter removal efficiency (99.98%), low pressure drop (68 Pa), and high quality factor Q_F (0.125 Pa^-1). In addition, the filtration mechanism of the PASS nanofibrous membrane was intuitively revealed by simulating the intercepted particular distributions and motion paths of particles. After a simple oxidation treatment, the O-PASS nanofibrous membrane was successfully built up. The microstructure and morphology showed little change compared with the PASS nanofiber, but the oxidation treatment significantly improved the mechanical properties of the membrane from 1.51 MPa to 4.92 MPa. More importantly, the O-PASS nanofibrous membrane still exhibited high removal efficiency after high temperature, acid, alkali, or organic solvent treatments. Overall, O-PASS nanofibrous membranes are promising high-performance filter materials with high temperature and corrosion resistance.

Functionalized electrospun nanofiber membranes for water treatment: A review

Electrospun nanofiber membranes (ENMs) have high porosity, high specific surface area and unique interconnected structure. It has huge advantages and potential in the treatment and recycling of wastewater. In addition, ENMs can be easily functionalized by combining multifunctional materials to achieve different water treatment effects. Based on this, this review summarizes the preparation of functionalized ENMs and its detailed application in the field of water treatment. First, the process and influence factors of electrospinning process are introduced. ENMs with high porosity, thin and small fiber diameter have better performance. Secondly, the modification methods of ENMs are analyzed. Pre-electrospinning and post-electrospinning modification technology can prepare specific functionalized ENMs. Subsequently, functionalized ENMs show water treatment capabilities such as separation, adsorption, photocatalysis, and antimicrobial. Subsequently, the application of functionalized ENMs in water treatment capabilities such as separation, adsorption, photocatalysis, and antimicrobial capabilities were listed. Finally, we also made some predictions about the future development direction of ENMs in water treatment, and hope this article can provide some clues and guidance for the research of ENMs in water treatment.