Ishikawa Ryo, Futazuka Toshihiro, Jimbo Yu, Kawahara Kazuaki, Shibata Naoya, Ikuhara Yuichi
Institute of Engineering Innovation, University of Tokyo, Bunkyo, Tokyo 113-8656, Japan.
EM Research and Development, JEOL Ltd., Akishima, Japan.
Sci Adv. 2024 Mar;10(9):eadk6501. doi: 10.1126/sciadv.adk6501. Epub 2024 Feb 28.
Single and multi-atoms supported on oxide substrates ultimately increase the efficiency of noble metal atom use, and moreover, catalytic activity and selectivity are also improved substantially. However, single and multi-atoms are unstable under catalytic conditions, and these metal atoms spontaneously aggregate and grow into nanoparticles. Catalytic performance is strongly related to local atomic configurations, and hence, it is essential to determine the three-dimensional (3D) atomic structures of multi-atoms on the substrate and their structural dynamics. Here, we show the real-time tracking of the 3D structural evolution of a Pt trimer on TiO (110) substrate at a high temperature, using high-spatiotemporal-resolution scanning transmission electron microscopy, where sub-angstrom spatial resolution is maintained, while the temporal resolution reaches 40 milliseconds. With the aid of prior structural knowledge of a Pt trimer for 3D reconstruction, the present method could open the way to characterize in situ atomic-scale structural dynamics, especially meta-stable structural transition.
负载在氧化物基底上的单原子和多原子最终提高了贵金属原子的使用效率，此外，催化活性和选择性也显著提高。然而，单原子和多原子在催化条件下不稳定，这些金属原子会自发聚集并生长成纳米颗粒。催化性能与局部原子构型密切相关，因此，确定基底上多原子的三维（3D）原子结构及其结构动力学至关重要。在这里，我们使用高时空分辨率扫描透射电子显微镜，展示了在高温下对TiO(110)基底上Pt三聚体的3D结构演化的实时跟踪，其中保持了亚埃空间分辨率，而时间分辨率达到40毫秒。借助Pt三聚体的先验结构知识进行3D重建，本方法可为原位原子尺度结构动力学，特别是亚稳结构转变的表征开辟道路。
