CHARACTERIZATION OF THICK-LAYER GRAPHITE DISPOSABLE VOLTAMMETRIC ELECTRODES

Graphite thick-film disposable electrodes which may be used for sensit ive analytical determinations by the techniques of conventional and st ripping voltammetry have been characterized by electron scanning micro scopy, optical spectroscopy, and electrochemical methods. Studies on t he reversible Cc(+) + e(-) reversible arrow Cc (Cc is cobaltocene) red uction process in acetonitrile confirmed the inlaid and recessed disk microelectrode random array-type behavior expected at a rough surface on the basis of examination of the electrode surface by electron scann ing microscopy. Anodic stripping voltammograms of copper, lead, and ca dmium in 0.1 M HCl at an in situ mercury-plated disposable graphite el ectrode demonstrate the excellent analytical performance that may be a chieved for trace analysis even at unusually fast scan rates in the vo lts per second range. The microelectrode array properties also mean th at oxygen removal and stirring of the solution can be avoided when the electrodes are used for stripping voltammetry.