Hydrogen Dissociation, Spillover, and Desorption from Cu-Supported Co Nanoparticles.
Co-Cu nanoparticles have recently been explored for Fischer-Tropsch synthesis (FTS) as a way to combine the long chain selectivity of Co with Cu's activity for alcohol formation in order to synthesize oxygenated transportation fuels. Depending on particle size, hydrogen dissociation can be a rate-determining step in cobalt-catalyzed FTS. To understand the fundamentals of uptake and release of hydrogen from the Co/Cu bimetallic system, we prepared well-defined Co nanoparticles on Cu(111). We demonstrate that hydrogen spills over from dissociation sites on the Co nanoparticles to the Cu(111) surface via the Co-Cu interface and that desorption of H occurs at a temperature that is lower than from Co or Cu alone, which we attribute to the Co-Cu interface sites. From this data, we have constructed an energy landscape for the facile dissociation, spillover, and desorption of hydrogen on the Co-Cu bimetallic system.
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States.
Emily A
EA
Lewis
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States.
Matthew D
MD
Marcinkowski
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States.
Colin J
CJ
Murphy
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States.
Melissa L
ML
Liriano
Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United States.
E Charles H
EC
Sykes
Fischer−Tropsch synthesis; STM; TPD; bimetallic; diffusion