Aging of starting solutions for nanoparticles synthesis with two different ultrasonication

Naoya Enomoto; Minami Matsuo; Miki Inada; Katsuro Hayashi; Junichi Hojo

doi:10.1016/j.ultsonch.2020.105142

Aging of starting solutions for nanoparticles synthesis with two different ultrasonication

Ultrason Sonochem. 2020 Oct:67:105142. doi: 10.1016/j.ultsonch.2020.105142. Epub 2020 Apr 24.

Authors

Naoya Enomoto¹, Minami Matsuo², Miki Inada³, Katsuro Hayashi⁴, Junichi Hojo⁴

Affiliations

¹ Department of Creative Engineering, National Institute of Technology, Ariake College, 150 Higashihagio, Omuta, Fukuoka 836-8585, Japan. Electronic address: enomoto@ariake-nct.ac.jp.
² Department of Creative Engineering, National Institute of Technology, Ariake College, 150 Higashihagio, Omuta, Fukuoka 836-8585, Japan.
³ Center of Advanced Instrumental Analysis, Kyushu University, Japan.
⁴ Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Japan.

PMID: 32361276
DOI: 10.1016/j.ultsonch.2020.105142

Abstract

Novel concept of aging starting solutions for nanoparticle synthesis and the application of two different sonication to aging is introduced. In sonoprocess of nanoparticles from liquid phase, it is usual to irradiate ultrasound to a reacting solution during synthesis. In this work, ultrasound is applied to a starting solution before synthesis. In case of the SiO₂ sphere synthesis, the aging process elongated the induction period of the precipitation, enlarge the sphere size, and enhanced the monodispersity of silica spheres. These effects were promoted by soft sonication at subtle power (~1 mW). In case of the TiO₂ sphere case, ordinary (cavitating) ultrasound during synthesis was found to be effective in more spherical shape. Also, the sonication to aging of the starting solution was useful for uniform spheres synthesis. Existence of miscible liquid such as water-ethanol and feasible relationship to the nucleation of nanoparticles are discussed.

Keywords: Alkoxide process; Ethanol-water mixture; Monodisperse sphere; Nucleation; Silica; Solution structure; Titania; Weak ultrasonication.