Electrodeposition of iridium in graphite tube as permanent chemical modifier in atomic absorption spectrometry Eletrodeposição de irídio em tubo de grafite como modificador químico permanente em espectrometria de absorção atômica

Naozuka J.; Oliveira P.V.; Pedrotti J.J.

Electrodeposition of iridium in graphite tube as permanent chemical modifier in atomic absorption spectrometry Eletrodeposição de irídio em tubo de grafite como modificador químico permanente em espectrometria de absorção atômica

Tipo

Artigo

Data de publicação

2003

Periódico

Quimica Nova

Citações (Scopus)

3

Autores

Naozuka J.
Oliveira P.V.
Pedrotti J.J.

Resumo

A tubular electrochemical flow-cell for iridium deposition on the inner surface of pyrolytic graphite tube for permanent chemical modification is proposed. A transversal heated graphite tube was used as working electrode, a cylindrical piece of graphite inserted into the graphite tube as auxiliary electrode, and a micro Ag/AgCl(sat) as reference electrode. Indium solution in 1.0 mol L-1 HCl, flowing at 0.55 mL min-1 for 60 min was used to perform the electrochemical modification. The applied potential to the flow-cell was - 0.700 V vs Ag/AgCl. Scanning electron microscopy images were taken for thermal and electrochemical modified graphite surface in order to evaluate the iridium distribution. Selenium hydride trapping was used to verify the performance of the proposed permanent chemical modifier.