화학공학소재연구정보센터
Electrochimica Acta, Vol.47, No.6, 899-904, 2001
Potential scan rate dependence of underpotential and bulk depositions of lead on screen-printed silver electrodes
This is the first report on studies or the underpotential deposition of Pb upd-Pb) on a disposable screen-printed silver electrode (AgSPE, non-single crystalline surface). The dependence of upd-Pb and bulk Pb deposition (bulk-Pb) on potential scan rate (nu) was demonstrated for the AgSPE in pH 3 KNO3/HNO3 solutions. At nu = 20 mV s(-1), the extent of formation of reversible upd-Pb was similar to 15 times less than that or irreversible bulk-Pb. However, for nu > 100 mV s(-1), only the upd-Pb was observed. Scanning electron microscopic (SEM) analysis speculated 3D-nucleation (hcp) of bulk-Pb on the AgSPE at low scan rate (nu = 1 mV s(-1)). On the other hand, at a raster scan rate (nu = 300 mV s(-1)), no marked crystallites were obtained. By interpretation with the CV results, the later case was proved to be formation and complete stripping of the upd-Pb on the AgSPE and this property was further utilized for analytical application. The nearly reversible behavior of the upd-Pb process at the disposable AgSPE is a judicious choice for the effective stripping analysis of Pb by square-wave voltammetry.