Polymeric materials as anion-exchange membranes for alkaline fuel cells

In recent decades, fuel cell technology has been undergoing revolutionary developments, with fundamental progress being the replacement of electrolyte solutions with polymer electrolytes, making the device more compact in size and higher in power density. Nowadays, acidic polymer electrolytes, typically Nafion, are widely used. Despite great success, fuel cells based on acidic polyelectrolyte still depend heavily on noble metal catalysts, predominantly platinum (Pt), thus increasing the cost and hampering the widespread application of fuel cells. Here, we report a type of polymer electrolyte fuel cells (PEFC) employing a hydroxide ion-conductive polymer, quaternary ammonium polysulphone, as alkaline electrolyte and nonprecious metals, chromium-decorated nickel and silver, as the catalyst for the negative and positive electrodes, respectively. In addition to the development of a high-performance alkaline polymer electrolyte particularly suitable for fuel cells, key progress has been achieved in catalyst tailoring: The surface electronic structure of nickel has been tuned to suppress selectively the surface oxidative passivation with retained activity toward hydrogen oxidation. This report of a H2–O2 PEFC completely free from noble metal catalysts in both the positive and negative electrodes represents an important advancement in the research and development of fuel cells.

Alkaline Polymer Electrolyte Fuel Cells Completely Free From Noble Metal Catalysts

Overview of bacterial cellulose composites: a multipurpose advanced material.

Polyacrylonitrile-based nanofibers—A state-of-the-art review

In situ synthesis of silver-nanoparticles/bacterial cellulose composites for slow-released antimicrobial wound dressing.

Biosynthesis of bacterial cellulose/multi-walled carbon nanotubes in agitated culture

Cellulose synthesized by Acetobacter xylinum in the presence of multi-walled carbon nanotubes.

Magnetic poly(styrene-co-acrylic acid-co-acrylamide) microspheres were prepared by water-in-oil-in-water (W/O/W) miniemulsion polymerization of monomers in the presence of Fe3O4 nanoparticles. The copolymerizable monomers of acrylic acid and acrylamide were used not only to modify the surfaces of the microspheres with functional groups, but also to act as viscosity regulators to control the morphology and size of these microspheres. It was experimentally observed that the surfaces of these microspheres were functionalized with NH2 groups produced by copolymerization, the morphologies (sphere, ringlike, and one-hole) of the microspheres were controlled by the concentration of copolymerizable monomers, and all samples prepared were superparamagnetic. The possible mechanism of formation of these magnetic microspheres is also discussed.

Controllable preparation of magnetic polymer microspheres with different morphologies by miniemulsion polymerization

Polyacrylonitrile (PAN)/Fe3O4 composite nanofibers were prepared via the electrospinning of the PAN spinning solutions with magnetite Fe3O4 nanoparticles. The experimental results showed that the morphology and diameter of the nanofibers strongly depended upon concentrations of PAN and salt additives in the spinning solutions. A suitable PAN concentration and LiCl additives could effectively prevent the occurrence of beads in the electrospinning process and affected the diameters of the electrospun nanofibers. The breaking strength and breaking strain decreased when the magnetite Fe3O4 nanoparticles were incorporated. The prepared PAN/Fe3O4 nanofibers were superparamagnetic at room temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Preparation and properties of electrospun PAN/Fe3O4 magnetic nanofibers

Dispersion of carbon nanotubes in a polymer matrix is one of the most critical issues in carbon nanotube/polymer composites. In this paper we discuss the considerable improvement in the dispersion of multiwalled carbon nanotubes (MWNTs) in poly(vinyl alcohol) (PVA) matrix that was attained through gum arabic treatment. The mechanical properties of these MWNT/PVA composites show that only 2 wt% nanotube loading increases the tensile modulus by more than 130%.

Biao Wang

Papers

Biosynthesis of bacterial cellulose/multi-walled carbon nanotubes in agitated culture

Cellulose synthesized by Acetobacter xylinum in the presence of multi-walled carbon nanotubes.

Controllable preparation of magnetic polymer microspheres with different morphologies by miniemulsion polymerization

Preparation and properties of electrospun PAN/Fe3O4 magnetic nanofibers

Fabrication and Properties of Carbon Nanotube and Poly(vinyl alcohol) Composites