Particle Size and Surface Coverage Effects in the Stripping Voltammetry of Silver Nanoparticles: Theory and Experiment

Abstract

Theory is presented for a mathematical model that includes two-dimensional diffusion for the stripping of randomly distributed metal nanoparticles. Theoretical results are compared with the reversible and irreversible limits in the approximate analytical form derived by Brainina and co-workers ( Brainina K. Z. Brainina K. Z. Talanta197118513.. Brainina K. Z. Lesunova R. P. Brainina K. Z. Lesunova R. P. Zh. Anal. Khim.1974291302.. Brainina K. Z. Vydrevich M. B. Brainina K. Z. Vydrevich M. B. J. Electroanal. Chem.19811211.) when considering an average coverage of material across the whole electrode surface instead of the individual particle environments considered in the presented theory. Experimental results are reported for the stripping of different-sized silver nanoparticles (AgNPs) from a basal-plane pyrolytic graphite electrode in 0.1 M NaClO4. Different loadings (as measured by the stripping charge) for each size of nanoparticle were investigated. The theory presented was used to explain the observed experimental trends in stripping peak potential and indicates that the Ag/Ag+ couple has electrochemically reversible kinetics.

Get More Out of Your Data: A New Approach to Agglomeration and Aggregation Studies Using Nanoparticle Impact Experiments

“…Silver nanoparticles : Citrate‐capped Ag NPs were synthesised and washed according to15 and redispersed in ultrapure H 2 O containing NaC 6 H 7 O 7 (1×10 −6 M ) to prevent agglomeration. The NP shape and size was characterized by high‐resolution scanning electron microscopy (SEM; LEO Gemini 1530, Zeiss).…”

Nanoparticle modified electrodes: Surface coverage effects in voltammetry showing the transition from convergent to linear diffusion. The reduction of aqueous chromium (III) at silver nanoparticle modified electrodes

“…The potential was scanned negatively from 0 to À0.9 V (vs. SCE) at 50 mV s À1 . In the case of the AgNP-BPPG electrodes, silver loading was then quantified by stripping from the surface in NaClO 4 (0.1 M), by scanning positively from 0.1 to 1.0 V (vs. SCE) [19].…”

Einzelnachweis und elektrochemisch unterstützte Identifizierung adsorbierter Nanopartikel mit Oberflächenplasmonen‐Mikroskopie

“…Dieser Effekt wurde thermodynamisch analysiert und durch elektrochemische Experimente bestätigt. Allerdings scheint die Größenbestimmung der NPs mithilfe der Bildintensität (Abbildung , unten, Einschub) zuverlässiger zu sein als mithilfe der Potentialverschiebung, da es erhebliche Diskrepanzen zwischen den beobachteten Werten und den Literaturangaben sowie eine breite Verteilung dieses Wertes für einige NP‐Typen gibt (Abbildung ). Das Hauptaugenmerk der elektrochemischen Analyse liegt in diesem Fall auf der chemischen Bestimmung des NP‐Materials durch den charakteristischen Bereich des Auflösungspotentials.…”