3.3 Catalysis
Catalyst effectiveness is proportional to its exposed surface area, as
more sites are available for reaction. To minimize the costs of large
volumes of catalytic metal, an economical strategy for catalyst
synthesis is to deposit catalytic metal on an inexpensive inert
substrate with a high surface area to volume ratio such as carbon or a
biotemplate. However, biotemplated catalysts are more efficient; Pd
catalyst synthesized from TMV1cys immobilized on a gold substrate in a
nanostar configuration increased the reaction rate 68% relative to
commercial Pd/C catalyst of comparable size [58]. TMV-templated
catalysts are stable and can be recycled with negligible degradation in
performance over several cycles [4, 5, 58]. The superior performance
of TMV-templated catalyst is attributed primarily to two factors. One,
palladium particles mineralized on TMV tend to be more uniform as
compared to commercially available palladium catalyst supported on
carbon material leading to more efficient catalysis [58, 59]. And
secondly, fabrication of palladium on TMV does not use surfactants and
capping agents like the synthesis of traditional catalysts that can
block active sites [60]. Removal of these surfactants to rescue
catalysis is incomplete and adds to the cost of catalyst manufacture.
Thus, biotemplated catalysts are both more catalytically- and
economically- advantaged in many scenarios.