Size Dependant Electrochemical Behavior of Silver Nanoparticles with Sizes of 10, 20, 40, 80 and 107 nm

Abstract

The direct detection of metal nanoparticles is of high importance. Here we investigate inherent electrochemistry of silver nanoparticles of sizes 10, 40, 80 and 107 nm by means of cyclic voltammetry.Keywords: Silver nanoparticles, Size dependant electrochemical behavior DOI: 10.1002/elan.201100690 There is a high demand for facile direct detection of metallic nanoparticles (NPs) arising from various areas such as biosensing [1][2][3], water quality assessment [4] or toxicity studies [5,6]. Electrochemistry is a facile method for direct determination of a wide range of metal nanoparticles, for example gold [7,8], platinum [9], silver [10][11][12] or molybdenum [13]. The detailed investigation whether different sizes of the metal nanoparticles exhibit different electrochemical properties were carried out frequently, predominantly for Au, Pt and Ag nanoparticles. The electrochemical detection of metal nanoparticles can be carried in two formats: immobilizing the nanoparticles on the electrode surfaces [7,8,12,13] or direct detection of nanoparticles hitting the surface of the electrode [10,11]. Here we investigate the electrochemical behavior of silver nanoparticles of sizes 10-107 nm, following our previous study of size dependant response of Au NPs (2-50 nm) [8] and also Comptons previous study of size dependency of voltammetry of Ag NPs [14][15][16][17][18]. Comptons group demonstrated theoretically and experimentally that stripping potential of Ag NPs depends on the size of the particles [14]. We confine ourselves to the traditional method of immobilization of particular sized nanoparticles on the surface of the electrodes. We also purposely did not used electrochemically generated Ag NPs [19] as such generation of NPs leads to wide size distribution but rather commercially available Ag NPs with narrow size distribution.We studied the influence of the size of the silver nanoparticles upon their electrochemical behavior in 50 mM phosphate buffer (pH 7.4) using cyclic voltammetry. There is apparent feature of electrochemical dissolution (stripping) of silver nanoparticles on the electrode surface, at~+ 440 mV and reduction of the generated silver ions in the oxidative part of cycle from the solution at+ 100 mV. As it can be seen from the voltammograms, the behavior of various silver nanoparticles significantly differs, depending on the size of the nanoparticles. First observation one can make is that 10 and 40 nm Ag NPs exhibit two oxidative peaks, denoted as Ox 1 and Ox 2. While Ox 2 peak potential is cycle number independent and it is practically identical for both 10 and 40 nm Ag NPs (of 443 mV for 10 nm Ag NPs; and of 445 mV for 40 nm Ag NPs), the potential of the first oxidation peak (Ox 1) changes with consecutive scans, reflecting the fact that every cycle there is the reduction of the electrogenerated Ag + ions which results into the nucleation of silver nanostructures at GC and Ag NPs surfaces (note that during oxidation step not all silver is dissolved). Figure 2 shows that potential Ox 1 decr...

Retraction: Controllable Electrochemical Synthesis of Silver Nanoparticles on Indium‐Tin‐Oxide‐Coated Glass

“…[14] Furthermore, the electrochemical oxidation potentials of AgNPs were also dependent on their size. [15][16][17] On the otherh and, silver nanoclusters are more in favor of SERS enhancement because of the presence of hotspots on the clusters. [18][19][20] In some applicationssuch as catalysis, sensors, and solar batteries, the metal nanoparticles are required to be assembled or constructed on as olid support.…”

Liberação controlada em ureia revestida empregando um sistema polimérico acrilato com foco no íon amônio

“…A aplicação eletroanalítica de nanopartículas metálicas é uma área de grandes estudos 48 , sendo os metais mais comumente estudos o ouro 54,55 , prata 56,57 e platina 58,59 . Além disso, outros metais como paládio 60,61 , níquel 62,63 , cobre 64 A estrutura molecular da tetraciclina estudada nesta dissertação é exibida na Figura 1.…”

The unique electrochemical reactivity of small metal nanoparticles.

“…140 More recently, Kuo and Hwang showed by voltammetry that the oxidation potential of Ag NPs depends on the shape and follows the order of cubes > spheres > decahedrons > triangular plates. 141 Giovanni et al studied the sizedependent oxidation of Ag NPs of 10 to 107 nm in diameter 142 while Buttry and co-workers showed a negative shift in the oxidation potential of Pd NPs with decreasing size by voltammetry. 143 There has also been an enormous effort to study the electrochemical behavior of individual nanoparticles.…”

“…110 Other groups have also observed sizedependent metal NP oxidation. For example, Giovanni et al studied the sizedependent oxidation of Ag NPs of 10-107 nm in diameter, 159 while Buttry and co-workers showed a negative shift in the oxidation potential of Pd NPs with decreasing size by voltammetry. 160 Our group was the first to quantify the negative shift in the oxidation potential of Ag (8-50 nm diameter) 36 and Au (4 to 250 nm diameter) 37 as a function of size directly by voltammetry and compared the results to the theory develop by Plieth.…”

“…studied the size-dependent oxidation of Ag NPs of 10-107 nm in diameter, 159 while Buttry and co-workers showed a negative shift in the oxidation potential of Pd NPs with decreasing size by voltammetry. 160 Sieradzki and co-workers reported the early oxidation of < 4 nm diameter Pt NPs at potentials well below the bulk value.…”