Adhesion of Pt Nanoparticles Supported on γ-Al2O3 Single Crystal
Zhongfan Zhang, Long Li, and Judith C. Yang, “Adhesion of Pt Nanoparticles Supported on γ-Al2O3 Single Crystal” The Journal of Physical Chemistry. Volume 117, Number 41, Pages 21407-21412.
A model catalyst system of Pt nanoparticles (2–5 nm) dispersed on γ-Al2O3 (111) was prepared to study the support effects on nanoparticles shape and structure by cross-sectional high-resolution electron microscopy. A dewetting equilibrium shape of Pt nanoparticles was observed with a low-index plane orientation relation: Pt(111)∥γ-Al2O3(111) and Pt(100)∥γ-Al2O3(111). Lattice-matching epitaxy of Pt(110)∥γ-Al2O3(110) was found across their interface to maintain a minimum interface strain during particle growth. To quantitatively interpret the interfacial energy and adhesion energy of the nanoparticles, the Wulff–Kaischew theorem was applied by taking into account the γ-Al2O3 support modifications to the equilibrium shape of nanoparticles. The present approach quantitatively solved the adhesion energy of the particle/support and could help to interpret nanoparticles equilibrium shape and stability.