Amidoximated PAN nonwoven fabrics coordinated with Fe( iii ) as a photocatalyst for formaldehyde degradation by activating O ₂ under visible irradiation.

In order to improve the photocatalytic performance of g-C₃N₄, the g-C₃N₄/Ti₃C₂/Ag₃PO₄ S-type heterojunction catalyst was prepared by electrostatic assembly method, and then the g-C₃N₄/Ti₃C₂/Ag₃PO₄/PAN composite nanofiber membrane was prepared by electrospinning technology. The morphology and chemical properties of the nanofiber membrane were characterized by SEM, FTIR, and XRD, and the photocatalytic degradation of tetracycline hydrochloride (TC) in water by the nanofiber membrane was investigated. The results showed that g-C₃N₄/Ti₃C₂/Ag₃PO₄ could be successfully loaded on PAN and uniformly distributed on the surface of composite nanofiber membrane by electrospinning technology. Increasing the amount of loading and catalyst, lowering the pH value and TC concentration of the system were conducive to the oxidation and degradation of TC. The nano-fiber catalytic membrane had been recycled five times and found to have excellent photocatalytic stability and reusability. The study of catalytic mechanism showed that h⁺, •OH and •O₂⁻ were produced and participated in the oxidation degradation reaction of TC, and •O₂⁻ plays a major role in catalysis. Therefore, this work provides a new insight into the construction of high-performance and high-stability photocatalytic system by electrospinning technology.

Polyester/polyamide 6 hollow segmented pie bicomponent spunbond hydro-entangled microfiber nonwovens (PET/PA6) with a microfilament structure have recently emerged in many markets around the world due to their green, high-strength, and lightweight properties. However, PET/PA6 is highly hydrophobic, which inhibits its large-scale application at present. In order to enhance the hydrophilic performance of PET/PA6, many methods have been applied, but the effects are not obvious. Ultraviolet (UV) irradiation treatment has proven to be an effective method to improve the hydrophilicity of fabrics. Herein, the aim of this paper was to investigate hydrophilic modification of PET/PA6 by UV/TiO₂/H₂O₂. The effect of H₂O₂, nano-TiO₂, and UV irradiation time on the morphology, elemental composition, hydrophilic properties, and mechanical properties of PET/PA6 were systematically investigated. The results showed that the modified microfibers were coated with a layer of granular material on the surface. It was found that the C 1s peak could be deconvoluted into six components (C–C–C, C–C–O, O–C=O, N–C=O, N–C–C, and C–C=O), and a suitable mechanism was proposed. Moreover, the water contact angle of PET/PA6 modified by 90 min irradiation with UV/TiO₂/H₂O₂ decreased to zero in 0.015 s, leading to the water vapor transmission rate and the water absorption reaching 5567.49 g/(m²·24 h) and 438.81%, respectively. In addition, the modified PET/PA6 had an excellent liquid wicking height of 141.87 mm and liquid wicking rate of 28.37 mm/min.

Herein, poly (allylamine hydrochloride) (PAH)/ poly (styrene sulfonic acid) sodium salt (PSS) microcapsules of (PAH/PSS)₂PAH (P2P MCs) and (PAH/PSS)₂ (P2 MCs) were obtained by a layer-by-layer method. The P2 MCs show high adsorption capacity for Rhodamine B (642.26 mg/g) and methylene blue (909.25 mg/g), with an extremely low equilibrium adsorption time (~20 min). The P2P MCs exhibited high adsorption capacities of reactive orange K-G (ROKG) and direct yellow 5G (DY5G) which were 404.79 and 451.56 mg/g. Adsorption processes of all dyes onto microcapsules were best described by the Langmuir isotherm model and a pseudo-second-order kinetic model. In addition, the P2P MCs loaded with reactive dyes (P2P–ROKG), could further adsorb rhodamine B (RhB) dye, and P2 MCs that had adsorbed cationic MB dyes could also be used for secondary adsorption treatment of direct dye waste-water, respectively. The present work confirmed that P2P and P2 MCs were expected to become an excellent adsorbent in the water treatment industry.

PET/PA6, hollow, segmented-pie, microfiber nonwovens (PET/PA6 HSMNs) play an important role in a microfiber, synthetic leather base. Most of the current PET/PA6 HSMNs generally lack in hygiene performance. Moreover, there is an urgent need for the asymmetric wettability of PET/PA6 HSMNs to ensure the comfort of clothing. In this work, a novel, asymmetrically wettable, PET/PA6 HSMN with a gradient structure is proposed, which can regulate liquid adsorption and directional transport. An MOF-303 was successfully synthesized and loaded onto the PET/PA6 HSMN, which had been pre-treated with gradient hydrolysis under sulfuric acid. The droplet quickly permeated the modified PET/PA6 HSMN, and the droplet disappearance time decreased to 62.40 ms. The liquid strikethrough time of the modified PET/PA6 HSMN reached 5.16 s. The maximum adsorption capacity of the modified PET/PA6 HSMN was 68.161 mg/g, which was improved by 122.83%. In addition, the air permeability of the pre-treated PET/PA6 HSMN increased from 308.70 mm/s to 469.97 mm/s, with the sulfuric acid concentrations increasing from 0% to 20%, and the air permeability of the modified PET/PA6 HSMN decreased gradually from 247.37 mm/s to 161.50 mm/s. Furthermore, the tensile strength of the modified PET/PA6 HSMN treated with sulfuric acid and MOF-303 was also obviously enhanced compared with the PET/PA6 HSMN treated with pure sulfuric acid. This PET/PA6 HSMN, with asymmetric wettability, owing to its high hygiene performance and water transport capabilities, is promising and able to extend the application of a microfiber synthetic leather base for clothing.

Hemin possesses great potential in eliminating organic pollutants due to its mild reaction condition, light-harvesting efficiency, and environmental friendliness. However, it has drawbacks such as being easy to aggregate and hard to recycle, and poor stability should be improved in practical application. Herein, the subject developed an electrospinning approach to enable the hemin particulates to be immobilized onto polyacrylonitrile (PAN) nanofibers stably. Hydrogen peroxide (H₂O₂) was adopted as an oxidant in the system to simulate the enzymatic catalysis of hemin in an organism. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflection spectroscopy (DRS), and electron spin resonance spectroscopy (ESR) analysis was employed to discuss the morphology, structure, and mechanism of the prepared n-hemin/PAN nanocomposite membranes, and 0.02 mmol L⁻¹ of the rhodamine B (RhB) removal activity in different conditions was also verified with these membranes. The kinetic studies showed that n-hemin/PAN nanocomposite membranes maintained excellent properties both in adsorption and degradation. Around 42% RhB could be adsorbed in the dark, while 91% RhB decolorized under xenon lamp irradiation in 110 min, suggesting the catalytic performance of n-hemin/PAN was greatly driven by light irradiation. Differing from the axial coordinated hemin complexes, n-hemin/PAN would catalyze hydrogen peroxide into •OH radicals rather than •OOH and high-valent metal-oxo species. This work provides an effective way to support hemin as nanocomposite membranes, in which the molecular interaction between polymer and hemin made their light adsorption an obvious red shift.