Density functional theory study of the interaction of H2O, CO2 and Co with the ZrO2 (111), Ni/ZrO2 (111), YSZ (111) and Ni/YSZ (111) surfaces

SURFACE SCIENCE

卷:653

Article

Cadi-Essadek, Abdelaziz¹  Roldan, Alberto²  de Leeuw, Nora H.^1,2 

[1] UCL, Dept Chem, 20 Gordon St, London WC1H 0AJ, England

[2] Cardiff Univ, Sch Chem, Main Bldg,Pk Pl, Cardiff CF10 3AT, S Glam, Wales

关键词: Triple phase boundary;    Yttria-stabilized zirconia;    Molecule-surface interaction;    Fuel cell;    Supported nanoparticles;    Surface science;   

DOI  :  10.1016/j.susc.2016.06.008

来源: Elsevier

【 摘 要 】

The triple phase boundary (TPB), where the gas phase, Ni particles and the yttria-stabilised zirconia (YSZ) surface meet, plays a significant role in the performance of solid oxide fuel cells (SOFC). Indeed, the key reactions take place at the TPB, where molecules such as H2O, CO2 and CO interact and react. We have systematically studied the interaction of H2O, CO2 and CO with the dominant surfaces of four materials that are relevant to SOFC, i.e. ZrO2( 111), Ni/ZrO2(111), YSZ(111) and Ni/YSZ(111) of cubic ZrO2 stabilized with 9% of yttria (Y2O3). The study employed spin polarized density functional theory (DFT), taking into account the long-range dispersion forces. We have investigated up to five initial adsorption sites for the three molecules and have identified the geometries and electronic structures of the most stable adsorption configurations. We have also analysed the vibrational modes of the three molecules in the gas phase and compared them with the adsorbed molecules. A decrease of the wavenumbers of the vibrational modes for the three adsorbed molecules was observed, confirming the influence of the surface on the molecules' intra-molecular bonds. These results are in line with the important role of Ni in this system, in particular for the CO adsorption and activation. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.

【 授权许可】

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