(212a) Platinum Monolayer Electrocatalysts: Further Improvements Using Novel High Stability, Low Cost Supporting Cores

Platinum Monolayer Electrocatalysts: Further improvements using  novel high stability, low cost supporting cores

Radoslav R.  Adzic

Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, U.S.A.

adzic@bnl.gov

Although considerable advances in developing fuel cell catalysts were made over the last fifteen years, the amount of platinum used in electrocatalysts for the oxygen-reduction reaction (ORR) at fuel-cell cathodes remains a challange because of its insufficient catalytic activity and stability. Pt monolayer electrocatalysts offer several uniquely attractive properties to meet that challenge, including an ultra-low Pt content, the 100% Pt utilization and very high activity. Further improving of these electrocatalysts can be achieved by using novel high stability, low cost cores such as: i) Nitride containing non–noble metal, or non-noble metal alloy cores, ii) Au- stabilized non-noble metal alloy cores, iii) Ordered intermetallic compounds iv) Refractory metals codeposited Ni alloys and v) Graphene as support.

Distinct classes of the ORR core-shell electrocatalysts result from these modifications of cores.   

Significantly enhanced the ORR activity as well as the durability of these catalysts is a consequence of combined geometrical, electronic and segregation effects on the Pt shells. The roles of each component in the catalyst was investigated and in the best case the catalyst showed a Pt group metal mass activity that was approximately 3 times higher than that of the commercial Pt/C electrocatalyst.

We recenly demonstrated extraordinary effects of strained Pt monolayer on Au on the kinetics of methanol and ethanaol oxidation. Details of these findings will be discussed at  the conference.