(October 8, 2015) While
the cleaning of car exhausts is among the best known applications of catalytic
processes, it is only the tip of the iceberg. Practically the entire chemical
industry relies on catalytic reactions. Catalyst design plays a key role in
improving these processes. An international team of scientists has now
developed a concept that elegantly correlates geometric and adsorption
properties. They validated their approach by designing a new platinum-based
catalyst for fuel cell applications.
Hydrogen would be an ideal energy carrier: Surplus wind
power could split water into its elements. The hydrogen could power fuel
cell-driven electric cars with great efficiency. While the only exhaust would
be water, the range could be as usual. But fuel cell vehicles are still a rare
exception. The required platinum (Pt) is extremely expensive and the world’s
annual output would not suffice for all cars.
A key component of the fuel cell is the platinum catalyst
that is used to reduce oxygen. It is well known that not the entire surface but
only a few particularly exposed areas of the platinum, the so-called active
centers, are catalytically active.
A team of scientists from Technical University of Munich and
Ruhr University Bochum (Germany), the Ecole normale superieure (ENS) de Lyon,
Centre national de la recherche scientifique (CNRS), Universite Claude Bernard
Lyon 1 (France) and Leiden University (Netherlands) have set out to determine
what constitutes an active center.