A common single-site Pt(II)-O(OH)x- species stabilized by sodium on "active" and "inert" supports catalyzes the water-gas shift reaction.
While it has long been known that different types of support oxides have different capabilities to anchor metals and thus tailor the catalytic behavior, it is not always clear whether the support is a mere carrier of the active metal site, itself not participating directly in the reaction pathway. We report that catalytically similar single-atom-centric Pt sites are formed by binding to sodium ions through -O ligands, the ensemble being equally effective on supports as diverse as TiO2, L-zeolites, and mesoporous silica MCM-41. Loading of 0.5 wt % Pt on all of these supports preserves the Pt in atomic dispersion as Pt(II), and the Pt-O(OH)x- species catalyzes the water-gas shift reaction from ∼120 to 400 °C. Since the effect of the support is "indirect," these findings pave the way for the use of a variety of earth-abundant supports as carriers of atomically dispersed platinum for applications in catalytic fuel-gas processing.
†Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States.
Ming
M
Yang
†Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States.
Jilei
J
Liu
‡X-ray Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States.
Sungsik
S
Lee
†Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States.
Branko
B
Zugic
§School of Chemical and Biomolecular Engineering, University of Sydney, Sydney, NSW 2006, Australia.
Jun
J
Huang
∥Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Lawrence F
LF
Allard
†Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States.
Maria
M
Flytzani-Stephanopoulos