Abstract

Atom-resolved characterization on the growth and structure evolution of nanocrystals

Author(s): Rongming Wang

Nanoscale characterization has enabled the discovery of many novel functional materials which started from understanding important relationships between material properties and morphologies. Therefore, nanoscale characterization has become an important research topic in nanoscience. Here we demonstrate the research of the growth and structure evolution of transition metal nanocrystals at atomic scale.

Revealing the catalyst structure and chemistry in the reactive environment at the atomic scale is imperative for the rational design of catalysts. Here, tracking intermetallic Co7W6 nanoparticles with a defined structure and a high melting point by environmental aberration-corrected transmission electron microscope, we directly present the structural and chemical stability of the Co7W6 nanocrystals in methane, carbon monoxide, and hydrogen at the temperature of 700–1100

The morphology and structural stability of metal/2D semiconductor interfaces strongly affect the performance of 2D electronic devices and synergistic catalysis. Here we study the structural evolution of Au nanoparticles on few-layer MoS2 by high resolution transmission electron microscopy (HRTEM) and quantitative high-angle annular dark field scanning TEM. It is found that in the transition of Au from nanoparticles to dendrites, a dynamically epitaxial alignment between Au and MoS2 lattices is formed, and Moiré patterns can be directly observed in HRTEM images due to the mismatch between Au and MoS2 lattices.