High-specific-surface-area magnetic porous carbon microspheres (MPCMSs) were fabricated by annealing Fe(2+)-treated porous polystyrene (PS) microspheres, which were prepared using a two-step seed emulsion polymerization process. The resulting porous microspheres were then sulfonated, and Fe(2+) was loaded by ion exchange, followed by annealing at 250 °C for 1 h under an ambient atmosphere to obtain the PS-250 composite. The MPCMS-500 and MPCMS-800 composites were obtained by annealing PS-250 at 500 and 800 °C for 1 h, respectively. The iron oxide in MPCMS-500 mainly existed in the form of Fe3O4, which was concluded by characterization. The MPCMS-500 carbon microspheres were used as catalysts in heterogeneous Fenton reactions to remove methylene blue (MB) from wastewater with the help of H2O2 and NH2OH. The results indicated that this catalytic system has a good performance in terms of removal of MB; it could remove 40 mg L(-1) of MB within 40 min. After the reaction, the catalyst was conveniently separated from the media within several seconds using an external magnetic field, and the catalytic activity was still viable even after 10 removal cycles. The good catalytic performance of the composites could be attributed to synergy between the functions of the porous carbon support and the Fe3O4 nanoparticles embedded in the carrier. This work indicates that porous carbon spheres provide good support for the development of a highly efficient heterogeneous Fenton catalyst useful for environmental pollution cleanup.

A one-step thermal decomposition strategy, in which a novel reductant participated, was developed to prepare superparamagnetic nearly cubic monodisperse Fe 3 O 4 nanoparticles loaded on multiwall carbon nanotubes (MWCNTs/Fe 3 O 4 ). Subsequently, the as-prepared MWCNTs/Fe 3 O 4 nanocomposites were modified with 3-aminopropyltriethoxysilane (APTS) (MWCNTs/Fe 3 O 4 -NH 2 ). The materials were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM) and the BET surface area method. The results indicated that superparamagnetic Fe 3 O 4 nanoparticles were successfully loaded onto the surface of the MWCNTs, and APTS was also modified on the MWCNTs/Fe 3 O 4 magnetic nanocomposites. The two as-prepared magnetic nanocomposites were used as adsorbents to remove tetrabromobisphenol A (TBBPA) and Pb(II) from wastewater. The adsorption kinetics and adsorption isotherms of TBBPA and Pb(II) on the two asprepared adsorbents were studied at pH 7.0 and 5.3, respectively. It was revealed that MWCNTs/ Fe 3 O 4 -NH 2 performed better than the MWCNTs/Fe 3 O 4 nanocomposites for the adsorption properties of TBBPA and Pb(II). After adsorption, both adsorbents could be conveniently separated from the media by an external magnetic field within several seconds, and regenerated in 0.1 M NaOH solution.

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Novel core–shell polypyrrole/graphene oxide (PPy–GO) nanomaterials of uniform PPy nanospheres and GO have been synthesized by an in situ surface-initiated polymerization method.

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Bacterial cellulose/polyaniline (BC/PANI) nanocomposites display many potential applications in various fields. However, the conductivity and mechanical properties remain a challenge. Here, we developed a novel method to prepare BC/PANI nanocomposites via the chemical grafting of PANI onto epoxy modified BC (EBC), followed by the grafting of polyacrylamide (PAM). For comparison, an in situ BC/PANI sample was also prepared. The grafting reaction between PANI and EBC and the retention of PANI on EBC were confirmed by FTIR, X-ray photoelectron spectroscopy, and elemental analysis. The cross-section morphology of BC transformed into a three-dimensional and continuous network structure with the incorporation of PANI. The effects of epoxy and PAM contents on the morphology, conductivity, and mechanical properties of PANI-g-EBC and PANI-g-EBC3/PAM nanocomposites were investigated. Compared with those of the in situ BC/PANI sample, the conductivity of PANI-g-EBC increased from 0.12 to 1.08 S/cm, while the stress increased from 8.18 to 18.47 MPa. With the addition of PAM, the conductivity of PANI-g-EBC/PAM nanocomposite paper further increased to 1.43 S/cm, and the stress increased to 47.94 MPa. The conductivity of PANI-g-EBC3/PAM nanocomposites only decreased from 1.43 to 1.36 S/cm after refolding 160 times. PANI-g-EBC and PANI-g-EBC3/PAM nanofibers could be blended with conventional plant cellulose fiber to prepare flexible and high strength conductive composite paper.

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