A 'jump-to-coalescence' mechanism during nanoparticle growth revealed by in situ aberration-corrected transmission electron microscopy observations. (12th April 2016)

• Record Type: Journal Article
• Authors: Neng, Wan; Shuang-ying, Lei; Jun, Xu; Martini, Matteo
• Is Part Of: Nanotechnology. Volume 27:Number 20(2016)
• Publication Date: 2016-04-12
• Subjects: nanoparticle coalescence -- atomic dynamics -- in situ aberration-corrected TEM -- first-principles calculation; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/0957-4484/27/20/205605
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: In this work, we used in situ aberration-corrected transmission electron microscopy (AC-TEM) to observe the coalescence of gold nanoparticles. We observed a critical edge-to-edge distance d e c ∼ 0.5 nm below which the two particles will coalesce rapidly (jump-to-coalescence). A model based on the single-atom-triggered rapid particle contraction was proposed and verified by first-principles calculations, in which evident energy decrease was detected when adding a gold atom between two gold nanoparticles. Our ex situ TEM study of sputtering-deposited gold nanoparticles on different substrates with varied time also supports the jump-to-contact mechanism. This observation afforded physical insight into the fundamental growth mechanism during dynamic particle coalescence processes.