TiO2-CNT composite as novel corrosion resistant PEMFC catalyst support
Date
2010-05
Authors
Journal Title
Journal ISSN
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Publisher
University of Delaware
Abstract
There is a need for novel materials to replace carbon black as platinum
catalyst support in PEMFC that are more resistant to corrosion by electrochemical
oxidation. The novel material investigated in this effort was Titania/multiwall carbon
nanotube composite. TiO2-MWCNT was synthesized using a surfactant assisted wet
chemical technique. The TiO2-MWCNT composite was obtained from chemical
reaction between TiCl4 and hydroxyl functionalized MWCNT. D.C electrical
conductivity vs. CNT content profiles showed adverse effects on conductivity beyond
17%. The addition of CNT conferred a maximum electrical conductivity of 0.87 S/cm,
a value less than the target of 1 S/cm but sufficient for the intended function. XRD
scans revealed the effective formation of anatase titania while the presence of CNT
was indicated by the black color in the final TiO2 composite and SEM. Cyclic
voltammetry scans at 8 hour-intervals, after oxidation at 1.2V vs. Ag/AgCl by
chronoamperometry technique, demonstrated the superior resistance to corrosion of
the synthesized TiO2-CNT as compared to commercial carbon black.