DEVELOPMENT AND SELECTION OF IONIC LIQUID ELECTROLYTES FOR HYDROXIDE CONDUCTING POLYBENZIMIDAZOLE MEMBRANES IN ALKALINE FUEL CELLS (open access)

DEVELOPMENT AND SELECTION OF IONIC LIQUID ELECTROLYTES FOR HYDROXIDE CONDUCTING POLYBENZIMIDAZOLE MEMBRANES IN ALKALINE FUEL CELLS

Alkaline fuel cell (AFC) operation is currently limited to specialty applications such as low temperatures and pure H{sub 2}/O{sub 2} due to the corrosive nature of the electrolyte and formation of carbonates. AFCs are the cheapest and potentially most efficient (approaching 70%) fuel cells. The fact that non-Pt catalysts can be used, makes them an ideal low cost alternative for power production. The anode and cathode are separated by and solid electrolyte or alkaline porous media saturated with KOH. However, CO{sub 2} from the atmosphere or fuel feed severely poisons the electrolyte by forming insoluble carbonates. The corrosivity of KOH (electrolyte) limits operating temperatures to no more than 80�C. This chapter examines the development of ionic liquids electrolytes that are less corrosive, have higher operating temperatures, do not chemically bond to CO{sub 2}, and enable alternative fuels. Work is detailed on the IL selection and characterization as well as casting methods within the polybenzimidazole based solid membrane. This approach is novel as it targets the root of the problem (the electrolyte) unlike other current work in alkaline fuel cells which focus on making the fuel cell components more durable.
Date: May 1, 2012
Creator: Fox, E.
System: The UNT Digital Library
METALLIC AND HYBRID NANOSTRUCTURES: FUNDAMENTALS AND APPLICATIONS (open access)

METALLIC AND HYBRID NANOSTRUCTURES: FUNDAMENTALS AND APPLICATIONS

This book chapter presents an overview of research conducted in our laboratory on preparation, optical and physico-chemical properties of metallic and nanohybrid materials. Metallic nanoparticles, particularly gold, silver, platinum or a combination of those are the main focus of this review manuscript. These metallic nanoparticles were further functionalized and used as templates for creation of complex and ordered nanomaterials with tailored and tunable structural, optical, catalytic and surface properties. Controlling the surface chemistry on/off metallic nanoparticles allows production of advanced nanoarchitectures. This includes coupled or encapsulated core-shell geometries, nano-peapods, solid or hollow, monometallic/bimetallic, hybrid nanoparticles. Rational assemblies of these nanostructures into one-, two- and tridimensional nano-architectures is described and analyzed. Their sensing, environmental and energy related applications are reviewed.
Date: May 2, 2012
Creator: Murph, S.
System: The UNT Digital Library