Electrochemical Nanoparticle Sizing Via Nano‐Impacts: How Large a Nanoparticle Can be Measured?

Abstract

The field of nanoparticle (NP) sizing encompasses a wide array of techniques, with electron microscopy and dynamic light scattering (DLS) having become the established methods for NP quantification; however, these techniques are not always applicable. A new and rapidly developing method that addresses the limitations of these techniques is the electrochemical detection of NPs in solution. The ‘nano-impacts’ technique is an excellent and qualitative in situ method for nanoparticle characterization. Two complementary studies on silver and silver bromide nanoparticles (NPs) were used to assess the large radius limit of the nano-impact method for NP sizing. Noting that by definition a NP cannot be larger than 100 nm in diameter, we have shown that the method quantitatively sizes at the largest limit, the lower limit having been previously reported as ∼6 nm.1

Bi2O3 Nanoparticle Clusters: Reversible Agglomeration Revealed by Imaging and Nano‐Impact Experiments

“…NTA analysis shows large proportions of clusters, which would be expected to be observed by impact voltammetry as estimated on the basis of their diffusion coefficients if they are present in the diffusion layer of the electrode . This observation is seemingly in contrast to that previously reported where agglomerates were detected in their clustered form .…”

Impact Electrochemistry of Layered Transition Metal Dichalcogenides

“…Despite the abovementioned limitations, this technique appears to be a viable method for size determination of particles even on a scale exceeding that achieved by prior studies, suggesting an upper detection limit of about 100 nm. 9 This finding serves as further testament to the high precision promised in earlier studies, although the shape and structure of the particles remain a crucial factor for consideration.…”

Impact and oxidation of single silver nanoparticles at electrode surfaces: one shot versus multiple events

“…In addition, the electrochemical oxidation of Ag NPs of 100 nm in diameter has led to peak currents spanning from 30–200 pA, 21 on the one hand, to 0.5–10 nA, 18 on the other, with an identical experimental configuration save for the use of different equipment to record the transients. This difference of almost 3 orders of magnitude in the peak currents for the anodic stripping of Ag NPs of the same size highlights the potential complexity of the stripping process, but raises significant questions on the effect of sampling rate and data filtering in the faithful acquisition of current transients.…”