H2O chemisorption and H2 oxidation on yttria-stabilized zirconia: Density functional theory and temperature-programmed desorption studies
H2O chemisorption and H2 oxidation on yttria-stabilized zirconia: Density functional theory and temperature-programmed desorption studies
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DOI：
10.1016/j.jpowsour.2010.09.090
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发表时间：
2011-09
影响因子：
9.2
通讯作者：
A. Gorski;Vitaliy Yurkiv;D. Starukhin;H. Volpp
中科院分区：
文献类型：
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作者：
A. Gorski;Vitaliy Yurkiv;D. Starukhin;H. Volpp
采用程序升温脱附（TPD）技术和密度泛函理论（DFT）研究了固体氧化物燃料电池（SOFC）阳极材料氧化钇稳定氧化锆（YSZ）上H2O的解离机理以及H2O的吸附和氧化反应.与理论一致的实验结果表明，气态H2O与YSZ的相互作用导致解离吸附，导致强烈结合的OH表面物种。在气态H2与富氧YSZ表面（YSZ+O）的相互作用中，形成类似的OH表面物种作为H2氧化的反应中间体。我们的实验表明，在H2O/YSZ和H2/YSZ+O非均相反应体系中，显著量的H2O作为间隙氢和羟基物质“溶解”在本体中。实验H2O解吸数据用于评估H2/H2O/YSZ吸附/解吸和表面反应动力学数据的准确性，所述数据用于Vogler等人在Ni图案/YSZ模型阳极上的电化学H2氧化的先前建模研究[J. Electrochem.索科，156（2009）B663]和Goodwin等人[J. Electrochem.索科，156（2009）B1004]。最后，一个完善的实验验证H2/H2O/YSZ吸附/脱附和表面反应动力学数据集。
The mechanism of H2O dissociation as well as the adsorption and oxidation reaction of H2on yttria-stabilized zirconia (YSZ), commonly used as part of solid oxide fuel cell (SOFC) anodes, was investigated employing temperature-programmed desorption (TPD) spectroscopy and density functional theory (DFT). In agreement with theory the experimental results show that interaction of gaseous H2O with YSZ results in dissociative adsorption leading to strongly bound OH surface species. In the interaction of gaseous H2with an oxygen-enriched YSZ surface (YSZ+O) similar OH surface species are formed as reaction intermediates in the H2oxidation. Our experiments showed that in both the H2O/YSZ and the H2/YSZ+O heterogeneous reaction systems noticeable amounts of H2O are “dissolved” in the bulk as interstitial hydrogen and hydroxyl species. The experimental H2O desorption data is used to access the accuracy of the H2/H2O/YSZ adsorption/desorption and surface reaction kinetics data, employed in previous modeling studies of the electrochemical H2oxidation on Ni-pattern/YSZ model anodes by Vogler et al. [J. Electrochem. Soc., 156 (2009) B663] and Goodwin et al. [J. Electrochem. Soc., 156 (2009) B1004]. Finally a refined experimentally validated H2/H2O/YSZ adsorption/desorption and surface reaction kinetics data set is presented.