In situ electron tomography for the thermally activated solid reaction of anaerobic nanoparticles

Abstract

A newly developed in situ electron tomography visualizes an entire process of Cu nanoparticle sintering in 4D (3D real space and time) from its very initial stage to the densification of nanoparticle clusters.

In-situ heating-and-electron tomography for materials research: from 3D (in-situ 2D) to 4D (in-situ 3D)

“…Here, we give a specific example of in-situ heating ET observation recently implemented by the authors’ group and show how these above-mentioned challenges were overcome. The observation target was the sintering process of Cu nanoparticles with an average particle size of 150 nm [ 14 ]. Sintering is one of the material processes that are now attracting attention in various fields, such as printed electronics, capacitors, batteries and thermoelectric materials, which can be a promising application of in-situ heating ET.…”

“… The specimen preparation/transfer/heating system for in-situ heating-and-ET observation of nanoparticles [ 14 ]. (a) All the sample preparation processes for the TEM observation were performed in an Ar gas-filled glove box.…”

“… Cu nanoparticles’ morphology variation [ 14 ]. (a) The relationship between the neck radius, r n , and the COM distance, d , by considering the aspect ratio, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} $H/W$\end{document} , of the targeted nanoparticle pairs, as explained in (d).…”

“…Here, we review our recent work in which our in-situ heating-and-ET method was applied to visualize the sintering behavior of Cu nanoparticles in four dimensions [ 14 ]. TEM-based methods are needed when the particle size gets smaller to the nanoscale due to the spatial resolution requirement.…”

“…Due to the technical innovations described above, in-situ heating-and-ET observation has gradually been applied to materials research, as demonstrated by several recent review papers from different groups [ 7 , 10–13 ]. This paper reviews the authors’ procedure of ET observation with specimen heating and its application to the sintering process of Cu nanoparticles [ 14 ] and focuses on the essential techniques that are indispensable for the 4D (space and time) imaging experiment.…”