Fabricating series of controllable-porosity carbon nanofibers-based palladium nanoparticles catalyst with enhanced performances and reusability

Amine-crosslinked lignin for water pollution attributable to organic dye remediation: Versatile adsorbent for selective dye removal and reusability

Lignin, an abundant natural resource, has not been effectively utilized. In this study, the functionality of lignin was enhanced through amination to produce amine-crosslinked lignin, and its adsorption behavior toward cationic and anionic dyes was investigated. Chemical structure analysis confirmed the successful introduction of amine groups, thereby improving the molecular weight and thermal stability of the optimized amine-crosslinked lignin. Additionally, the amine-crosslinked lignin exhibited a larger specific surface area than kraft lignin, as well as excellent adsorption capacity for both anionic and cationic dyes. Furthermore, it selectively adsorbed anionic and cationic dyes depending on pH conditions. The adsorption kinetics were described using a pseudo-second-order model, and the adsorption isotherms for congo red and methyl green were determined using the Langmuir and Freundlich equations, respectively. Additionally, the reusability and adsorption efficiency of the optimized amine-crosslinked lignin were evaluated, confirming its stable and repeatable adsorption efficiency for congo red and methyl green even after five repeated cycles. The assumed adsorption mechanism was attributed to electrostatic interactions. Therefore, the successful synthesis and excellent adsorption properties of amine-crosslinked lignin suggest its promising potential for environmentally friendly and efficient removal of both cationic and anionic dyes, thereby offering a sustainable solution for wastewater treatment and remediation.

Fabrication of Electrospun Polymer Nanofibers with Diverse Morphologies

Fiber structures with nanoscale diameters offer many fascinating features, such as excellent mechanical properties and high specific surface areas, making them attractive for many applications. Among a variety of technologies for preparing nanofibers, electrospinning is rapidly evolving into a simple process, which is capable of forming diverse morphologies due to its flexibility, functionality, and simplicity. In such review, more emphasis is put on the construction of polymer nanofiber structures and their potential applications. Other issues of electrospinning device, mechanism, and prospects, are also discussed. Specifically, by carefully regulating the operating condition, modifying needle device, optimizing properties of the polymer solutions, some unique structures of core⁻shell, side-by-side, multilayer, hollow interior, and high porosity can be obtained. Taken together, these well-organized polymer nanofibers can be of great interest in biomedicine, nutrition, bioengineering, pharmaceutics, and healthcare applications.

Fabrication of tubular braid reinforced PMIA nanofiber membrane with mussel-inspired Ag nanoparticles and its superior performance for the reduction of 4-nitrophenol

A novel tubular braid reinforced (TBR) PMIA/CA-PEI/Ag nanofiber membrane for application in dynamic catalysis was introduced in this study. The preparation method of the TBR PMIA/CA-PEI/Ag nanofiber membrane was facile and efficient. The TBR PMIA/CA-PEI/Ag nanofiber membrane was characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The mechanical properties were evaluated by a universal material testing machine. The tensile strength of TBR nanofiber membrane exceeded 500 MPa, whereas that of the nanofiber membrane without reinforcement was merely 10 MPa. Besides, the compressive strength of the TBR nanofiber membrane was also reinforced, which indicated that the TBR nanofiber membrane could withstand a higher operating pressure. The reduction of 4-NP to 4-AP was selected as the model reaction to evaluate the catalytic property of TBR PMIA/CA-PEI/Ag nanofiber membrane. The apparent rate constant of dynamic catalysis was 34.58 times higher than that of static catalysis. After 10 cycles, the conversion of 4-NP was still higher than 95.3%. This indicated that the TBR PMIA/CA-PEI/Ag nanofiber membrane had superior stability and recyclability. Besides, the TBR PMIA/CA-PEI/Ag nanofiber membrane also showed superior catalytic performance when it was used for catalyzing other environmental pollutants.

Fabrication of vanadium oxide, with different valences of vanadium, -embedded carbon fibers and their electrochemical performance for supercapacitor

Herein, composite materials, V_xO_y-embedded carbon fibers, were fabricated through a facile electrospinning method followed by calcination.

Preparation of Rh–SiO2 fiber catalyst with superior activity and reusability by electrospinning

Rh–SiO₂ fiber catalyst prepared by electrospinning for room temperature hydrogenation of alkenes with superior catalytic activity and reusability.