T RANSMISSION E LECTRON M ICROSCOPY OF S HAPE -C ONTROLLED N ANOCRYSTALS AND T HEIR A SSEMBLIES 班級 : 碩機一甲 姓名 : 蘇琬婷 學 號 :MA Z.L. Wang Structures of Individual Nanocrystals 電子顯微鏡學期末報告

Figure 5. (a) Geometrical shapes of cubo octahedral nanocrystals as a function of the ratio, R, of the growth rate along the to that of the. (b) Evolution in shapes of a series of (111) based nanoparticles as the ratio of {111} to {100} increases. The beginning particle is bounded by three {100} facets and a (111) base, while the final one is a {111} bounded tetrahedron. (c) Geometrical shapes of multiply twinned decahedral and icosahedral particles. Shapes of Individual Nanocrystals

Figure 6. HRTEM images of cubic Pt nanocrystals oriented along (a) [001] and (b) [110], showing surface steps/ledges and the thermodynamically inequilibrium shapes. Shapes of Individual Nanocrystals

Figure 7. HRTEM images of Pt nanocrystals (a) with a truncated octahedral shape and oriented along [110] and (b) with a octahedral shape and oriented along [110] and [001]. The inset in (a) is a model of the particle shape. Shapes of Individual Nanocrystals

Figure 8. HRTEM images of truncated tetrahedral Pt nanocrystals oriented along [110]. The surface steps and ledges at the truncated corners are clearly resolved. Shapes of Individual Nanocrystals