Abstract: | Decomposition of H2O2 with Fe2+ was studied with SnO2 electrodes. By chronoamperometric and voltammetric techniques, the diffusion coefficients of Fe3* and H 2O2 were estimated to be 5 × 10-6 and 2 × 10?5 cm2/s, respectively; the rate of decomposition of H2O2 with Fe2+ was proportional to [H2O2]1/2·[Fe2+]2 at a smaller concentration of Fe2+, but to [H2O2]1/2·[Fe2+] when [Fe2+] was increased, indicating the formation of ferryl ion and the electron exchange between it and Fe2+ playing important roles. This catalytic decomposition. was dependent on pH; the maximum rate was observed to occur about pH = 1.5. |