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Polymer nanocomposites containing pristine (PCNF) and amine‐functionalized (NFCNF) electrospun carbon nanofibers were fabricated. The amine‐terminated functional groups on CNFs, with a surface coverage of 2.76 mmol/g, react with the epoxy monomers forming covalent linkages for better dispersion and stronger interface. The improved load transfer resulted in an improvement of 82% in storage modulus (rubbery region~70°C) and 20°C increase in the glass transition temperature for 1 wt% NFCNF‐epoxy. Tensile strength and modulus improves by 22% and 27%, respectively, for 2 wt% NFCNF‐epoxy. The thermal stability, dielectric properties and AC/DC conductivity are discussed in terms of the interfacial characteristics. These results highlight the potential of electrospun CNFs as structural and functional reinforcement. [ABSTRACT FROM AUTHOR]

We report the synthesis of titania nanofibers (TNF) of ∼195 nm mean diameter doped with phosphorus through one‐pot electrospinning followed by decoration of Ag nanoparticles (NPs). The Ag NPs of ∼8 nm size on 2 % P‐doped TNFs (Ag‐PTNFs) showed excellent photocatalytic activity for the reduction of Cr(VI), under simulated solar light, with ∼100 % conversion to Cr(III) in 90 min at pH 3 with a pseudo‐first order rate constant of 0.085 min−1 that is 96.5 % higher than TNFs. The Ag‐PTNFs also exhibited excellent photodegradation of methylene blue with pseudo‐first order rate constant of 0.052 min−1 which is 82.7 % better than TNFs. The enhanced photocatalytic performance of Ag‐PTNFs is attributed to the reduced band‐gap, increased charge separation and reduced recombination rates. A proposed photocatalytic mechanism based on the synergistic effect of both Ag and P doping is presented which highlights the potential of these composite materials for water remediation. [ABSTRACT FROM AUTHOR]

Abstract: Strong carbon nanofibers with diameters between 150nm and 500nm and lengths of the order of centimeters were realized from electrospun polyacrylonitrile (PAN). Their tensile strength reached a maximum at 1400°C carbonization temperature, while the elastic modulus increased monotonically until 1700°C. For most carbonization temperatures, both properties increased with reduced nanofiber diameter. The tensile strength and the elastic modulus, measured from individual nanofibers carbonized at 1400°C, averaged 3.5±0.6GPa and 172±40GPa, respectively, while some nanofibers reached 2% ultimate strain and strengths over 4.5GPa. The average tensile strength and elastic modulus of carbon nanofibers produced at 1400°C were six and three times higher than in previous reports, respectively. These high mechanical property values were achieved for optimum electrospinning parameters yielding strong PAN nanofibers, and optimum stabilization and carbonization temperatures, which resulted in smooth carbon nanofiber surfaces and homogeneous nanofiber cross-sections, as opposed to a previously reported core–shell structure. Turbostratic carbon crystallites with average thickness increasing from 3 to 8 layers between 800°C and 1700°C improved the elastic modulus and the tensile strength but their large size, discontinuous form, and random orientation reduced the tensile strength at carbonization temperatures higher than 1400°C. [Copyright &y& Elsevier]

• Graphitic carbon nitride loaded titania nanofibers as z-scheme photocatalysts. • Synergistic effect by surface plasmon resonance of silver nanoparticles. • Photodegradation of organic dyes and photoreduction of heavy metal ions. • Bactericidal efficiency against E. coli and S. aureus. • Hierarchical multi-functional nanofiber based materials for water remediation. Here, we report synergistic sensitization of electrospun TiO 2 nanofibers (TNFs) by heterojunction formation with exfoliated g-C 3 N 4 nanosheets and decorated with Ag nanoparticles (NPs) uniformly over its surface for enhanced photocatalytic activity in simulated solar light. These composite catalysts displayed first-order rate constants of 0.087 min−1 and 0.031 min−1 for photodegradation of methylene blue (MB) and photoreduction of Cr(VI) under simulated sunlight which is 75% and 87% higher than the pristine TNFs, respectively, and better than the previously reported results for similar materials. Moreover, 99% of E. coli and 83% S. aureus were inactivated after 60 min of irradiation. The enhanced activities of these prepared ternary composite nanofibers are attributed to the effective Z-scheme heterojunction formation between TiO 2 and g-C 3 N 4 due to the preferred band positions which facilitates the charge transfer and inhibit the recombination of charge carriers. Moreover, visible-light harvesting, charge separation and antimicrobial nature of these nanofibers were promoted by the Ag NPs due to the surface plasmon resonance (SPR) effect. [ABSTRACT FROM AUTHOR]