title: Selective hydrogen production from formic acid decomposition on Pd-Au bimetallic surfaces.
abstract: Pd-Au catalysts have shown exceptional performance for selective hydrogen production via HCOOH decomposition, a promising alternative to solve issues associated with hydrogen storage and distribution. In this study, we utilized temperature-programmed desorption (TPD) and reactive molecular beam scattering (RMBS) in an attempt to unravel the factors governing the catalytic properties of Pd-Au bimetallic surfaces for HCOOH decomposition. Our results show that Pd atoms at the Pd-Au surface are responsible for activating HCOOH molecules; however, the selectivity of the reaction is dictated by the identity of the surface metal atoms adjacent to the Pd atoms. Pd atoms that reside at Pd-Au interface sites tend to favor dehydrogenation of HCOOH, whereas Pd atoms in Pd(111)-like sites, which lack neighboring Au atoms, favor dehydration of HCOOH. These observations suggest that the reactivity and selectivity of HCOOH decomposition on Pd-Au catalysts can be tailored by controlling the arrangement of surface Pd and Au atoms. The findings in this study may prove informative for rational design of Pd-Au catalysts for associated reactions including selective HCOOH decomposition for hydrogen production and electro-oxidation of HCOOH in the direct formic acid fuel cell.
authors.affiliation: McKetta Department of Chemical Engineering and Department of Chemistry, Center for Nano and Molecular Science and Technology, Texas Materials Institute, and Center for Electrochemistry, University of Texas at Austin , Austin, Texas 78712, United States.
authors.forename: Wen-Yueh
authors.initials: WY
authors.lastname: Yu
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Mullen
authors.forename: David W
authors.initials: DW
authors.lastname: Flaherty
authors.forename: C Buddie
authors.initials: CB
authors.lastname: Mullins