Precisely tailored synthesis of hexagonal hollow silica plate particles and their polymer nanocomposite films with low refractive index

Kiet Le Anh Cao; Shuto Taniguchi; Tue Tri Nguyen; Aditya F Arif; Ferry Iskandar; Takashi Ogi

doi:10.1016/j.jcis.2020.03.064

Precisely tailored synthesis of hexagonal hollow silica plate particles and their polymer nanocomposite films with low refractive index

J Colloid Interface Sci. 2020 Jul 1:571:378-386. doi: 10.1016/j.jcis.2020.03.064. Epub 2020 Mar 19.

Authors

Kiet Le Anh Cao¹, Shuto Taniguchi¹, Tue Tri Nguyen¹, Aditya F Arif², Ferry Iskandar³, Takashi Ogi⁴

Affiliations

¹ Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan.
² Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan; Department of New Investment, P.T. Rekayasa Industri Holding Company, Jl. Kalibata Timur I No. 36, Jakarta 12740, Indonesia.
³ Department of Physics, Institute of Technology Bandung, Ganesha 10, Bandung 40132, West Java, Indonesia.
⁴ Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan. Electronic address: ogit@hiroshima-u.ac.jp.

PMID: 32220680
DOI: 10.1016/j.jcis.2020.03.064

Abstract

Hollow silica particles are desirable for numerous applications, however, designing hollow silica materials with varying hollow structures and shapes remains a significant challenge. Herein, a strategy for the precisely controlled synthesis of hexagonal-shaped hollow silica plate (HHSP) particles was successfully prepared via a sol-gel method at room temperature, using tetraethyl orthosilicate (TEOS) as a silica precursor and zinc oxide (ZnO) particles as a colloidal template. The effect of reaction time was carried out to control the structure and morphology of HHSP particles, and the thickness of silica shell can be tuned in the range from 12.2 to 43.2 nm by adjusting the TEOS/ZnO molar ratios. In addition, the polymer/HHSP composite thin films were prepared using poly(methyl methacrylate) (PMMA) matrix and surface modified HHSP particles by grafting silane coupling agents. High transmittance values were observed (>95%) for the composite thin films (5 μm in thickness, 0.1-1.0 wt% HHSP) in the ultraviolet and visible regions. Furthermore, the refractive index of HHSP particles was observed to be 1.28, which is significantly lower than dense silica (n = 1.46). These results suggest that the approach adopted herein will open up opportunities for the development of a new generation of film materials with a low refractive index.

Keywords: Hollow silica plate; Nanostructured particles; Polymer nanocomposite; Refractive index; Sol-gel method.