The electrochemical reduction of hydrogen peroxide on uranium dioxide electrodes in alkaline solution

The electrochemical reduction of hydrogen peroxide on SIMFUEL electrodes in alkaline sodium chloride solution has been studied. Using the steady-state polarization technique, Tafel slopes and reaction orders with respect to H2O2 have been determined. The results have been interpreted in terms of a chemical–electrochemical mechanism involving UIV/UV donor–acceptor reaction sites. The large values of the Tafel slopes and the fractional reaction orders can be understood in terms of the potential-dependent surface coverage of active sites, similar to that observed in the reduction of hydrogen peroxide on oxidized copper surfaces. The effects of pH in the range 10–13 were also investigated.