Elucidating the role of electrophoretic mobility for increasing yield in the electrophoretic deposition of nanomaterials

Prabal Tiwari; Noah D Ferson; Jennifer S Andrew

doi:10.1016/j.jcis.2020.02.103

Elucidating the role of electrophoretic mobility for increasing yield in the electrophoretic deposition of nanomaterials

J Colloid Interface Sci. 2020 Jun 15:570:109-115. doi: 10.1016/j.jcis.2020.02.103. Epub 2020 Feb 27.

Authors

Prabal Tiwari¹, Noah D Ferson², Jennifer S Andrew³

Affiliations

¹ Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, United States. Electronic address: prabal.tiwari93@gmail.com.
² Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, United States. Electronic address: noah.ferson@ufl.edu.
³ Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, United States. Electronic address: jandrew@mse.ufl.edu.

PMID: 32145650
DOI: 10.1016/j.jcis.2020.02.103

Abstract

Hypothesis: Catalysts, chemical, gas, and bio- sensing devices fabricated from porous nanoparticle films show better performance and sensitivity than their bulk material counterparts because of their high specific surface area. Electrophoretic deposition (EPD) technique is a cost-effective, fast, versatile, and easy to perform method to fabricate porous nanoparticle films. However, conventional EPD is currently limited by the fact that the deposition rate decreases with time, resulting in an eventual plateau in the deposit yield. Here, we sought to overcome this limitation by establishing and leveraging the critical role of the particle's electrophoretic mobility in EPD kinetics.

Experiments: To identify the impact of electrophoretic mobility on EPD yield we used alumina nanoparticles suspended in ethanol as a model system. Changes in particle mobility were monitored via changes in the effective pH (pHe) of the suspension during EPD. We also developed a new suspension replenish EPD approach that allows us to maintain near-constant particle mobility and particle concentration with time thereby increasing yield.

Findings: We observed that in conventional EPD the particle mobility of the alumina nanoparticles decreased with time, resulting in a halting of deposition. Further, using the suspension replenish EPD, we observed a linear increase in the mass of the deposited film with time, overcoming the plateau limitation of conventional EPD.

Keywords: Alumina; EPD; Electrophoretic deposition; Electrophoretic deposition kinetics; Electrophoretic mobility; Materials assembly; Nanoparticle films; Particle mobility; Porous films; Scalable nanomanufacturing.