Accurate Nanoparticle Size Determination using Electrical Mobility Measurements in the Step and Scan Modes

Published

October 12, 2022

Author(s)

Kaleb Duelge, George Mulholland, Vincent A. Hackley, Michael Zachariah

Abstract

A critical and extensive comparison was made between differential mobility analysis (DMA) measurements of the mean diameter of monodisperse gold nanoparticles (AuNP), based on step-voltage mode and the more commonly used scan-voltage mode (commercially known as scanning mobility particle sizer, SMPS). Under specific conditions, the difference between the two modes of operation were less than the combined uncertainty for the step-voltage mode. Additionally, a comparison was made between two different calibration methods for DMA: the use of a certified nanoparticle size standard (artifact) versus a direct measurement of the sheath flow rate. Important variables and limitations for accurate measurements by the scan-voltage method were identified and evaluated. The mean size shifts to smaller diameters as the scan time is reduced and the scan mode is unable to measure sufficient points across the peak of very narrow size distributions, leading to systematic errors. Conversely, the speed of the scan-voltage mode can be an advantage and allow for a faster data collection rate for distributions that are changing rapidly with time. A methodology was presented for the use of these and other monodisperse calibration particles for accurately calibrating SMPS instruments for the measurement of the mobility diameter distribution.

Citation

Aerosol Science and Technology

Volume

56

Issue

12

Pub Type

Journals

Download Paper

https://doi.org/10.1080/02786826.2022.2128986

Local Download

Keywords

differential mobility, particle size, aerosol, nanoparticle, gold, calibration, metrology, scanning mobility, step mode

Citation

Duelge, K. , Mulholland, G. , Hackley, V. and Zachariah, M. (2022), Accurate Nanoparticle Size Determination using Electrical Mobility Measurements in the Step and Scan Modes, Aerosol Science and Technology, [online], https://doi.org/10.1080/02786826.2022.2128986, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=934801 (Accessed April 18, 2024)