High-Throughput Nanoparticle Characterization via Glow Discharge Optical Emission Spectroscopy Elemental Mapping

Abstract

Nanoparticle (NP) characterization is critical in many fields due to the use of NPs in numerous applications. Traditional NP characterization techniques, however, are limited by low sample throughput, and few can measure the size and elemental composition. Furthermore, sample throughput limitations are compounded in elemental mapping (EM) techniques for obtaining NP spatial distribution. Glow discharge optical emission spectroscopy (GDOES) EM can provide large area maps directly and cost-effectively from solid samples within tens of seconds. Here, GDOES EM is demonstrated for the first time for NP characterization in terms of mass, elemental composition, and size/structure dimensions. The effects of GD pulsed power, pressure, and sample substrate were studied, and optimized conditions resulted in limits of detection at single pg levels. While this is not at the level of single nanoparticle sensitivity, size differentiation of Ag and Au nanoparticles was successfully demonstrated between 5 and 100 nm, while the internal dimensions of complex core–shell NPs were also identified through the optical emission changes as a function of time.

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…GD-OES elemental mapping can provide large area maps directly and cost-effectively from solid samples within tens of seconds. The benefits of the approach to the characterisation of NPs in terms of mass, elemental composition and size/structure dimensions were demonstrated for Ag and Au NPs by Finch et al 46 The effects of GD pulsed power, pressure, and sample substrate were studied, and optimised conditions resulted in LODs at single pg levels. While this is not at the level of single NP sensitivity, size differentiation of Ag and Au NPs was successfully demonstrated between 5 and 100 nm, while the internal dimensions of complex core–shell NPs were also identified through the optical emission changes as a function of time.…”