In situ Reduction and Oxidation of Nickel from Solid Oxide Fuel Cells in a Transmission Electron Microscope
In situ Reduction and Oxidation of Nickel from Solid Oxide Fuel Cells in a Transmission Electron Microscope
复制标题
在透射电子显微镜下对固体氧化物燃料电池中的镍进行原位还原和氧化
DOI：
--
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
A. Hessler
中科院分区：
文献类型：
--
作者：
A. Faes;Q. Jeangros;J. Wagner;T. Hansen;J. herle;A. Brisse;R. Dunin‐Borkowski;A. Hessler
使用环境透射电子显微镜对 Ni/YSZ 固体氧化物燃料电池阳极支撑件在 300-500°C 温度下的镍还原和氧化进行原位表征。还原反应在低氢气压力下进行。还原从 NiO/YSZ 界面开始，然后移动到 NiO 晶粒的中心。在较高温度下，还原也会发生在自由 NiO 表面和 NiO/NiO 晶界处。 Ni 的生长是在其氧化物上外延生长的。由于体积大量减少，在还原过程中形成纳米孔。氧化过程中，镍表面形成氧化物纳米微晶。微晶填充镍孔隙并形成具有剩余空隙的不均匀结构。这种结构变化导致氧化镍在 RedOx 循环期间膨胀。
Environmental transmission electron microscopy was used to characterize in situ the reduction and oxidation of nickel from a Ni/YSZ solid oxide fuel cell anode support between 300-500°C. The reduction is done under low hydrogen pressure. The reduction initiates at the NiO/YSZ interface, then moves to the center of the NiO grain. At higher temperature the reduction occurs also at the free NiO surface and the NiO/NiO grain boundaries. The growth of Ni is epitaxial on its oxide. Due to high volume decrease, nanopores are formed during reduction. During oxidation, oxide nanocrystallites are formed on the nickel surface. The crystallites fill up the nickel porosity and create an inhomogeneous structure with remaining voids. This change in structure causes the nickel oxide to expand during a RedOx cycle.