The effects of simulated fission products in the reduction of hydrogen peroxide on simulated nuclear fuel electrodes

The electrochemical reduction of hydrogen peroxide (H2O2) has been studied on a series of simulated nuclear fuel (SIMFUEL) materials with different amounts of simulated fission products. Steady-state polarization measurements under diffusion-compensated conditions show that the reaction proceeds with a weak dependence on applied potential and fractional reaction orders with respect to H2O2. A mechanism for H2O2 reduction on SIMFUEL materials is proposed to explain these features. It is found that the activity of the material for the H2O2 reduction reaction increases with the doping level. This increase can be attributed to noble metal particles present in the SIMFUEL. This enhanced reactivity is most apparent at low overpotentials, where H2O2 reduction proceeds significantly faster on the noble metal particles than on the UO2+x lattice. (c) 2006 The Electrochemical Society.