Department of Chemical Engineering and Materials Science, University of California-Davis, One Shields Avenue, Davis, California 95616, USA.
Nat Nanotechnol. 2010 Dec;5(12):843-7. doi: 10.1038/nnano.2010.234. Epub 2010 Nov 21.
To fully understand the properties of functional nanostructures such as catalytic nanoclusters, it is necessary to know the positions of all the atoms in the nanostructure. The catalytic properties of metal nanoclusters can often be improved by the addition of a second metal, but little is known about the role of the different metals in these bimetallic catalysts, or about their interactions with each other and the support material. Here we show that aberration-corrected scanning transmission electron microscopy of supported rhodium-iridium clusters, combined with dynamic multislice image simulations, can identify individual atoms, map the full structure, and determine changes in the positions of metal atoms in sequential images. This approach could help in the development of new and improved catalysts and other functional nanostructures.
要全面了解功能纳米结构（如催化纳米簇）的性质，就必须知道纳米结构中所有原子的位置。添加第二种金属通常可以提高金属纳米簇的催化性能，但对于这些双金属催化剂中不同金属的作用，或者它们之间以及与载体材料的相互作用，人们知之甚少。在这里，我们展示了结合了动态多层面像模拟的、带有像差校正的支撑铑-铱团簇扫描透射电子显微镜术，可以识别单个原子、绘制完整结构，并确定在连续图像中金属原子位置的变化。这种方法有助于开发新的和改进的催化剂以及其他功能纳米结构。
