Search

Compared with traditional metal materials, carbon-based materials have the advantages of low density, high conductivity, good chemical stability, etc., and can be used as reliable alternative materials in various fields. Among them, the carbon fiber conductive network constructed by electrospinning technology has the advantages of high porosity, high specific surface area and rich heterogeneous interface. In order to further improve the conductivity and mechanical properties of pure carbon fiber films, tantalum carbide (TaC) nanoparticles were selected as conductive fillers. The crystallization degree, electrical and mechanical properties of electrospun TaC/C nanofibers at different temperatures were investigated. As the carbonization temperature increases, the crystallization degree and electrical conductivity of the sample also increases, while the growth trend of electrical conductivity is markedly slowed. The best mechanical properties of 12.39 MPa was achieved when the carbonization temperature was 1200 °C. Finally, through comprehensive analysis and comparison, it can be concluded that a carbonization temperature of 1200 °C is the optimum. [ABSTRACT FROM AUTHOR]

Abstract: Copolymers, poly(acrylonitrile-co-monobutylitaconate-co-n-butylacrylate) (copolyacrylonitrile, co-PANs) with different content of monobutyl itaconate (MBI) were synthesized by free radical polymerization and then electrospun into aligned nanofibers. After thermal treatments of stabilization, carbonization, and graphitization, the resulting aligned co-PAN nanofibers were converted to aligned electrospun carbon nanofiber bundles (ECNFB) with diameters of approximately 200nm. FT-IR technique was applied to investigate the stabilization process of co-PAN nanofibers, while XRD, TEM and tensile tester were used to characterize the microstructures and mechanical properties of the ECNFB. The measured results revealed that MBI was a fairly useful comonomer for preparing high performance PAN-based CNFs by improving the stabilization of co-PAN nanofibers and by promoting the formation of ordered graphite crystals in the ECNFB. When the content of MBI unit in co-PAN was 5wt%, the aligned ECNFB exhibited a tensile strength of up to 1.8GPa and a Young׳s modulus of up to 97.0GPa, which is 86% and 67% higher than those of the ECNFB previously reported in our group respectively. [Copyright &y& Elsevier]

A reusable magnetic WC-Co composite (Co/C-1000) filter with efficient water treatment was prepared by in-situ growth of ZIF-67 on the inside and outside surface of wood following by carbonization. [Display omitted] • Magnetic WC-Co composite is designed for wastewater treatment. • WC-Co composite has ultra-high dyes adsorption capacity. • The Co/C-1000 filter has good removal efficiency for high dye concentration solution at a higher flux. • The Co/C-1000 filter with excellent thermal stability can be recycled by simple burning method. Organic dye in water is a crucial global environmental problem. Notably, dyes, especially anionic dye Congo red (CR) and cationic dye Methylene blue (MB), have carcinogenic and mutagenic effects on human health. However, the commercial activated carbon with bad reusability is difficult to collect, which results in poor actual adsorption. In this paper, ZIF-67@wood obtained by in situ growth of ZIF-67 on wood is carbonized to prepare magnetic WC-Co composites. The hierarchical porous structure of wood can facilitate the rapid passage of dye solution, and promote full contact between magnetic core–shell Co/C nanoparticles and dyes. The adsorption capacities of CR and MB by Co/C-1000 are 1117.03 and 805.08 mg g−1, respectively. The pH pzc (7.9) of Co/C-1000 is then determined. When the dye concentration reaches 1200 mg L−1, the removal efficiency of Co/C-1000 reaches 99.98% under gravity. With the flux of 1.0 × 104 L m−2h−1 for CR solution (100 mg L−1), the removal efficiency of Co/C-1000 filter connected with peristaltic pump is almost 99.28%. In addition, the Co/C-1000 filter with high reusability and the adsorbed dyes can be removed by simple burning. This economical, recyclable and self-supporting filter with ultra-high adsorption capacity feature has the potential to replace commercial activated carbon and it will be widely used in practical wastewater treatment. [ABSTRACT FROM AUTHOR]