Treatments with organic surfactants, followed by the deposition of nanocrystalline ceria coatings from aqueous solution, were applied to anodes of solid oxide fuel cells. The cells were then operated in hydrogen/nitrogen fuel streams with H2S contents ranging from 0 to 500 ppm. Two surfactant treatments were studied: immersion in dodecanethiol, and a multi-step conversion of a siloxy-anchored alkyl bromide to a sulfonate functionality.
View Article and Find Full Text PDFMesoporous solid solutions of anatase-based titanium-vanadium oxides were synthesized from aqueous solutions. The V/Ti ratio was determined by the composition of the deposition solution, while the morphology and nanoscale porosity were controlled using micelles of the surfactants cetyltrimethylammonium bromide (CTAB), or hexadecylamine (HDA). The use of CTAB resulted in mesoporous powders, whereas HDA yielded clusters of nanotubes.
View Article and Find Full Text PDFSiloxane-anchored, self-assembled monolayers (SAMs) on single crystal Si were prepared with a variety of surface functional groups using a single commercially available surfactant (1-bromo-11-(trichlorosilyl)undecane) followed by in situ transformations. Polar (thioacetate and thiol), nonpolar (methyl), acidic (sulfonic and carboxylic), basic (various amines), and ionic (alkylammonium) surface functionalities were prepared. For primary amine and sulfonate surfaces, the degree of surface charge as a function of pH was determined ex situ using X-ray photoelectron spectroscopy (XPS).
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