E-viri
Recenzirano Odprti dostop
  • Characterizing Substrate–Su...
    Perras, Frédéric A; Padmos, J. Daniel; Johnson, Robert L; Wang, Lin-Lin; Schwartz, Thomas J; Kobayashi, Takeshi; Horton, J. Hugh; Dumesic, James A; Shanks, Brent H; Johnson, Duane D; Pruski, Marek

    Journal of the American Chemical Society, 02/2017, Letnik: 139, Številka: 7
    Journal Article

    The characterization of nanometer-scale interactions between carbon-containing substrates and alumina surfaces is of paramount importance to industrial and academic catalysis applications, but it is also very challenging. Here, we demonstrate that dynamic nuclear polarization surface-enhanced NMR spectroscopy (DNP SENS) allows the unambiguous description of the coordination geometries and conformations of the substrates at the alumina surface through high-resolution measurements of 13C–27Al distances. We apply this new technique to elucidate the molecular-level geometry of 13C-enriched methionine and natural abundance poly­(vinyl alcohol) adsorbed on γ-Al2O3-supported Pd catalysts, and we support these results with element-specific X-ray absorption near-edge measurements. This work clearly demonstrates a surprising bimodal coordination of methionine at the Pd–Al2O3 interface.