Electrochemical Detection of Low Concentrations of Mercury in Water Using Gold Nanoparticles.

Citation:

Ratner N, Mandler D. Electrochemical Detection of Low Concentrations of Mercury in Water Using Gold Nanoparticles. Anal. Chem. (Washington, DC, U. S.)Analytical Chemistry (Washington, DC, United States). 2015;87 (10) :5148 - 5155.

Date Published:

2015///

Abstract:

The electrochem. detection of Hg in aq. solns. was studied at glassy C (GC) and In-Sn oxide (ITO) electrodes modified by Au nanoparticles (Au NPs). Two methods of modification were used: electrochem. redn. of HAuCl4 and electrostatic adsorption of Au NPs stabilized by citrate. We found that the Au NPs modified surfaces yielded higher sensitivity and sharper and more reproducible stripping peaks of Hg as compared with the bare electrodes. The effect of the modification by Au NPs on the stripping potential was examd. Interestingly, the stripping of Hg on GC and ITO modified by Au NPs occurred at the same potential as on bare GC and ITO, resp. Only the full coverage of ITO by either electrochem. deposited Au for a long time or by vapor deposition, shifted the stripping potential more pos. by ∼0.4 V to that obsd. on a bare Au electrode. These and further expts. led us to conclude that the Au NPs served as nucleation sites for the deposition of Hg, whereas the GC or ITO are superior for the stripping of Hg. Hence, a combination of well-defined Au NPs on ITO or GC were found ideal for the electrochem. detection of Hg. We achieved a remarkable detection limit of 1 μm/L of Hg using an ITO surface modified by electrostatically adsorbed Au NPs. [on SciFinder(R)]

Notes:

CAPLUS AN 2015:667448(Journal; Online Computer File)