Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Feb 8;11(2):427.
doi: 10.3390/nano11020427.

Novel Surfactant-Free Water Dispersion Technique of TiO2 NPs Using Focused Ultrasound System

Seon Ae Hwangbo  1 , Minjeong Kwak  1 , Jaeseok Kim  1 , Tae Geol Lee  1
Affiliations

Novel Surfactant-Free Water Dispersion Technique of TiO2 NPs Using Focused Ultrasound System

Seon Ae Hwangbo et al. Nanomaterials (Basel). .

Abstract

Titanium dioxide (TiO2) nanoparticles are used in a wide variety of products, such as renewable energy resources, cosmetics, foods, packaging materials, and inks. However, large quantities of surfactants are used to prepare waterborne TiO2 nanoparticles with long-term dispersion stability, and very few studies have investigated the development of pure water dispersion technology without the use of surfactants and synthetic auxiliaries. This study investigated the use of focused ultrasound to prepare surfactant-free waterborne TiO2 nanoparticles to determine the optimal conditions for dispersion of TiO2 nanoparticles in water. Under 395-400 kHz and 100-105 W conditions, 1 wt% TiO2 colloids were prepared. Even in the absence of a surfactant, in the water dispersion state, the nanoparticles were dispersed with a particle size distribution of ≤100 nm and did not re-agglomerate for up to 30 days, demonstrating their excellent dispersion stability.

Keywords: TiO2 colloid; colloid stability; pH; particle size distribution; ultrasonic dispersion; zeta potential.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1
Figure 1
Schematic of the ultrasonic dispersion equipment employed in this study.
Figure 2
Figure 2
Aerial cross-sectional view of the ultrasonic dispersion equipment and the dimensions of the focused ultrasonic field.
Figure 3
Figure 3
Sound pressure (left) and energy (right) distribution models of the focused ultrasound radiation.
Figure 4
Figure 4
Three-dimensional sound field modeling of the focused ultrasound radiation.
Figure 5
Figure 5
Process of cavitation generation and collapse via ultrasound.
Figure 6
Figure 6
SEM images before (a) and after (b) ultrasonic dispersion. (a-1) and (b-1) represent the magnified images of the regions marked in white boxes in (a) and (b), respectively.
Figure 7
Figure 7
TEM images before (a) and after (b) ultrasonic dispersion.
Figure 8
Figure 8
Particle size and size distributions of TiO2 particles for different ultrasonic exposure times (samples 1 (black, 0 min), 2 (yellow, 15 min), 3 (blue, 84 min), and 4 (red, 120 min)).
Figure 9
Figure 9
Changes in pH and zeta potentials of TiO2 colloid samples such as sample 1 (0 min), sample 2 (15 min), sample 3 (84 min), and sample 4 (120 min) after various ultrasonic wave exposure times.
Figure 10
Figure 10
Particle size, size distributions, and stability of TiO2 colloids with DSE values of (a) 234, (b) 1363, and (c) 1947 J/mL.
See this image and copyright information in PMC

References

    1. Chen X., Mao S.S. Titanium dioxide nanomaterials: Synthesis, properties, modifications, and applications. Chem. Rev. 2007;107:2891–2959. doi: 10.1021/cr0500535. - DOI - PubMed
    1. Haidera A.J., Al-Anbari R.H., Kadhim G.R., Salame C.T. Exploring potential Environmental applications of TiO2 Nanoparticles. Energy Procedia. 2017;119:332–345. doi: 10.1016/j.egypro.2017.07.117. - DOI
    1. Sato K., Li J.-G., Kamiya H., Ishigaki T. Ultrasonic dispersion of TiO2 nanoparticles in aqueous suspension. J. Am. Ceram. Soc. 2008;91:2481–2487. doi: 10.1111/j.1551-2916.2008.02493.x. - DOI
    1. Sumitomo S., Koizumi H., Azhar Uddin M., Kato Y. Comparison of dispersion behavior of agglomerated particles in liquid between ultrasonic irradiation and mechanical stirring. Ultrason. Sonochem. 2018;40:822–831. doi: 10.1016/j.ultsonch.2017.08.023. - DOI - PubMed
    1. Inkyo M., Tahara T., Iwaki T., Iskandar F., Hogan C.J., Jr., Okuyama K. Experimental investigation of nanoparticle dispersion by beads milling with centrifugal bead separation. J. Colloid Interface Sci. 2006;304:535–540. doi: 10.1016/j.jcis.2006.09.021. - DOI - PubMed

LinkOut - more resources