open access

https://hdl.handle.net/2115/97551

Transmission Electron Microscopy Imaging of Cluster Unit Dissolution from a Single Crystal of Tetra-n-butylammonium Fluoride Semiclathrate Hydrate for Latent-Heat Storage Material

英語

crystal growth

2025-03-09

American Chemical Society

ACS Applied Nano Materials

アクセプト後にタイトル変更あり、著者最終稿は変更前のタイトル"TEM Imaging of Cluster Unit Dissolution from a Single Crystal of Tetra-n-butylammonium Fluoride Semiclathrate Hydrate for Latent-Heat Storage Material"

A nonclassical phase-transition model in which clusters act as the growth units has gained acceptance, contrasting with the classical phase-transition model where atoms or molecules attach or detach individually. However, this cluster-based model for phase transitions has not been established in phase transitions of semiclathrate hydrates, latent-heat storage materials, in which cage structures form and dissociate at the crystal surface. Using liquid-cell transmission electron microscopy, we directly observed the dissociation behavior of a single crystal of tetra-n-butylammonium fluoride semiclathrate hydrate induced by electron-beam irradiation. Early dissociation stages showed moire patterns, indicating that a 10-30 nm region of the crystal surface had transitioned to a metastable phase. Subsequently, spherical clusters, potentially responsible for the memory effect that facilitates recrystallization after dissociation, appeared without diffraction contrast attributable to crystal. These observations provide insights into nonclassical dissociation processes of hydrates to understand the phase transition of latent-heat storage materials.

学術雑誌論文

Accepted Manuscript

This document is the Accepted Manuscript version of a Published Work that appeared in final form in 'ACS Applied Nano Materials', copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/articlesonrequest/AOR-YKATKFAHWU7UIDWT9MMY.