Electrocatalytic reactions of hydrogen peroxide at carbon paste electrodes modified by some metal hexacyanoferrates

Carbon paste electrodes (CPE's), modified by ferrous, cupric, cuprous, cobalt and nickel hexacyanoferrates, were shown to electrocatalyse the cathodic reduction of hydrogen peroxide. At pH 3.05 ferrous hexacyanoferrate (FHC) modified CPE shows a cathodic response of 0.2 mA/cm(2) to 1 mM of peroxide added. By increasing the solution pH the response of this CPE diminishes drastically (by two orders of magnitude at pH 7.3). In contrast, the cupric hexacyanoferrate (CHC) modified CPE shows a high cathodic response in the whole pH range investigated, 3.05-7.3. (C) 1998 Elsevier Science S.A. All rights reserved.