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A novel β-phase polyvinylidene difluoride (PVDF) nanofibrous membrane decorated with multiwalled carbon nanotubes (MWCNTs) and platinum nanoparticles (PtNPs) was fabricated by an improved electrospinning technique. The morphology of the fabricated PVDF-MWCNT-PtNP nanofibrous membrane was observed by scanning electron microscopy, and the formation of high β-phase in the hybrid nanofibrous membrane was investigated by Fourier transform infrared spectroscopy and differential scanning calorimetry. The uniform dispersion of MWCNTs and PtNPs in the PVDF hybrid nanofibrous membrane and their interaction were explored by transmission electron microscopy and X-ray diffraction. For the first time, we utilized this created PVDF-MWCNT-PtNP nanofibrous membrane for biosensor and catalysis applications. The nonenzymatic amperometric biosensor with highly stable and sensitive, and selective detection of both H2O2 and glucose was successfully fabricated based on the electrospun PVDF-MWCNT-PtNP nanofibrous membrane. In addition, the catalysis of the hybrid nanofibrous membrane for oxygen reduction reaction was tested, and a good catalysis performance was found. We anticipate that the strategies utilized in this work will not only guide the further design of functional nanofiber-based biomaterials and biodevices but also extend the potential applications in energy storage, cytology, and tissue engineering.

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Biosorption of Cu 2+ and Pb 2+ by Cladophora fascicularis was investigated as a function of initial pH, initial heavy metal concentrations, temperature and other co-existing ions. Adsorption equilibriums were well described by Langmuir and Freundlich isotherm models. The maximum adsorption capacities were 1.61 mmol/g for Cu 2+ and 0.96 mmol/g for Pb 2+ at 298 K and pH 5.0. The adsorption processes were endothermic and biosorption heats calculated by the Langmuir constant b were 39.0 and 29.6 kJ/mol for Cu 2+ and Pb 2+ , respectively. The biosorption kinetics followed the pseudo-second order model. No significant effect on the uptake of Cu 2+ and Pb 2+ by co-existing cations and anions was observed, except EDTA. Desorption experiments indicated that Na 2 EDTA was an efficient desorbent for the recovery of Cu 2+ and Pb 2+ from biomass. The results showed that Cladophora fascicularis was an effective and economical biosorbent material for the removal and recovery of heavy metal ions from wastewater.