第一性原理研究由金属镍和钇稳定的氧化锆所形成的三相边界微观结构

摘要

基于第一性原理计算并结合经典的蒙特卡罗方法对镍团簇在钇稳定的氧化锆(YSZ)表面的各种稳定吸附构型进行了结构搜索，并得到了不同于以往文献中报道的更稳定的三相边界构型。在此基础上，对氧迁移时所伴随的电荷转移进行了深入的探讨。这里，从YSZ到Ni上的电子转移是描述固体氧化物燃料电池阳极电化学反应的关键，因此，我们进一步分析了影响电荷转移量的可能因素。所得研究结果暗示着在SOFC阳极可能存在着新的电化学反应机制。%Using the classical Monte Carlo method and density functional theory (DFT) calculations, various stable adsorption configurations for the Ni/yttria-stabilized zirconia anode (Ni/YSZ) were predicted. Compared with previously reported results, more stable triple phase boundary structures were found. Based on these optimized configurations, charge transfer is discussed in detail, as O ion migration occurs where electron transfer from YSZ to Ni is important in describing the electrochemical reaction at the anodes of the solid oxide fuel cells. We thus analyzed the possible factors that affect the degree of electron transfer. The results indicate that a new electrochemical mechanism is at work in the Ni/YSZ system.