Naslov
Voltammetry as a tool for detecting metal sulfide particles and nanoparticles in natural waters

Autori
Bura-Nakić, Elvira ; Krznarić, Damir ; Geroge R., Helz ; Ciglenečki, Irena

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Goldschmidt Conference Abstracts 2007 / - , 2007

Skup
Goldschmidt 2007 - "atoms to planets"

Mjesto i datum
Köln, Njemačka, 17.08.2007. - 24.08.2007

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
voltammetry; metal sulfide particles and nanoparticles

Sažetak
This paper deals with voltammetric characterization of metal sulfide particles and nanoparticles (PbS, HgS, FeS, CdS, Ag2S and CuS) at the Hg and the glassy carbon electrodes in 0.55 M NaCl + 0.03 M NaHCO3 electrolyte, pH = 8.5. The aim was to investigate a possibility of using voltammetry in the detection of metal-sulfide nanoparticles in natural waters. The proposed electrochemical approach was applied in the detection of metal sulfide particles in two stratified lakes: saline Rogoznica Lake on the eastern Adriatic coast and Lake Pavin, a crater lake in the Central Massif, France. The results of this work demonstrate that Pb, Hg, Fe, Cd, Ag and Cu sulfides, either as suspended powders or as precipitated nanoparticles, yield cathodic peaks between .0.9 and .1.7 V. Different experimental conditions (i.e. ageing of the particles, deposition potential and accumulation time) can affect shapes and positions of these reduction peaks. In anoxic natural samples, reduction peaks similar to those observed in model solutions were detected suggesting that voltammetry is a promising method for determination of metal sulfide nanoparticles. However, reduction peaks in the same potential range have been observed by other authors, who assigned them to the reduction of multimeric FeS(aq) complexes or clusters. The key findings of this work that other analytes: Cu2S, CuS, PbS, HgS, CdS, Ag2S nanoparticles, metal sulfide powders and sulfur powder produce similar reduction peaks. Therefore, here, we propose an experimental procedure to clarify the origin of voltammetric peak around -1.1 V in anoxic natural waters.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

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