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Centre researchers are intensively studying the process of
electrocatalysis. As oxidation and reduction can be carried out
using only electrons as reagents, this field holds promise for
the development of "green chemistry". Centre research
focuses on three areas: zeolite dispersion electrolysis, thin
film photo-electrocatalysis, and glassy metals.
 Zeolites
Electrochemical processes occur at the boundary of the zeolite
particle; that is, the redox chemistry can occur in the cages
at the zeolite-solution-electrode interface. The controlled growth
of nano-sized catalytic metals and oxides offers a viable way
to generate a new class of electrocatalytical systems. Another
promising area is the encapsulation of "ship-in-a-bottle"
catalysts in zeolites and enzymes in mesoporous hosts.
Glassy Metals
Researchers hope to prepare new catalysts for electrochemical
energy conversion in fuel cells, including binary alloys that
combine platinum and metals from groups IV and V (e.g. Sn., Bi,
Si, Ge, P). These alloys can be rapidly quenched to form thin
layers. By avoiding immiscibility gaps and surface segregation
that can limit catalytic performance, this process allows formation
of compositionally uniform catalysts. The oxidation of hydrogen,
carbon monoxide and methanol, and the reduction of oxygen on these
amorphous alloys, is important in assessing their relative performance
in fuel cell applications.
Metal Oxides
Titanium dioxide has found use as a photoelectrocatalyst in the
oxidation of organic pollutants in ground water. Centre researchers
are actively investigating the use of thin-film titanium dioxide
as an alternative to powder-based preparations. They are preparing
the active film on an inexpensive, inactive support using spray
pyrolysis. Much of the work in this area has involved either titanium
dioxide powder or pellets formed from the powder. Two key properties
of the film are its electrical conductivity and its porosity.
Conductivity is controlled by suitable doping, and high porosity
has been attained by control of the spray pyrolysis parameters.
Following preliminary studies by Pacific Technology showing that
the activity of the first Guelph films was 87% of the best anatase
TiO2 powder available, resarchers are now studying ways to improve
them.
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