Sampling for silver nanoparticles in aqueous media using a rotating disk electrode: evidence for selective sampling of silver nanoparticles in the presence of ionic silver

Abstract

Amendment of a carbon paste electrode consisting of graphite and Nujol®, with a variety of organic and inorganic materials, allows direct adsorption of silver nanoparticles (AgNPs) from aqueous solution in either open or close circuit modes. The adsorbed AgNPs are detected by stripping voltammetry. Detection limits of less than 1 ppb Ag are achievable with a rotating disk system. More than one silver peak was apparent in many of the stripping voltammograms. The appearance of multiple peaks could be due to different species of silver formed upon stripping or variation in the state of aggregation or size of nanoparticles. With most of these packing materials, dissolved Ag was also extracted from aqueous solution, but, with a packing material made with Fe(II,III) oxide nanoparticles, only AgNPs were extracted. Therefore, it is the best candidate for determination of metallic AgNPs in aqueous environmental samples without interference from Ag.

Platinum-Silver Alloy Nanoballoon Nanoassemblies with Super Catalytic Activity for the Formate Electrooxidation

“…The Pt–Ag ANBNSs were obtained through the galvanic reaction between K 2 PtCl 4 and Ag nanoflowers template and the subsequent oxidation etching process (Scheme ). The PtCl 4 2– /Pt redox couple has a higher Nernst potential (φ θ = 1.19 V) than that of the Ag I /Ag redox couple (φ θ = 0.8 V), which provides a driving of the galcanic reaction. Pt II ions contact the Ag surface and obtain the electrons from Ag.…”

Silver Nanoparticles and Ionic Silver Separation Using a Cation-Exchange Resin. Variables Affecting Their Separation and Improvements of AgNP Characterization by SP-ICPMS

“…For this reason, simpler and less expensive analytical tools for detecting, extracting, and/or preconcentrating AgNPs have been developed. Alternatives, such as stripping voltammetry or cyclic voltammetry, have been used to detect nanosilver in the presence of Ag + in real waters [ 41 , 42 , 43 ]. Sample pretreatment methods have also been employed in combination with the aforementioned analytical techniques.…”