The Institute of Scientific and Industrial Research, Osaka University , 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
Nano Lett. 2013 Jul 10;13(7):3073-7. doi: 10.1021/nl400919c. Epub 2013 Jun 24.
Aberration-corrected environmental transmission electron microscopy (ETEM) proved that catalytically active gold nanoparticles (AuNPs) move reversibly and stepwise by approximately 0.09 nm on a cerium oxide (CeO2) support surface at room temperature and in a reaction environment. The lateral displacements and rotations occur back and forth between equivalent sites, indicating that AuNPs are loosely bound to oxygen-terminated CeO2 and may migrate on the surface with low activation energy. The AuNPs are likely anchored to oxygen-deficient sites. Observations indicate that the most probable activation sites in gold nanoparticulate catalysts, which are the perimeter interfaces between an AuNP and a support, are not structurally rigid.
经像差校正的环境透射电子显微镜（ETEM）证明，在室温及反应环境下，催化活性金纳米粒子（AuNPs）在氧化铈（CeO2）载体表面可通过约 0.09nm 的距离进行可逆、分步运动。侧向位移和旋转在等效位置之间来回发生，表明 AuNPs 与氧终止的 CeO2 松散结合，并且可能在低活化能下在表面上迁移。AuNPs 可能锚定在氧空位上。观察表明，在金纳米颗粒催化剂中最可能的活化位，即 AuNP 和载体之间的边界界面，其结构并不稳定。
