It is shown that hydrogen evolution can be obtained far from equilibrium as an oscillating mechanism during the electrochemical reduction of hydrogen peroxide at copper-containing semiconductor electrodes. Periodic hydrogen evolution was experimentally verified by in-situ differential electrochemical mass spectroscopy (DEMS). We report a working mechanistic model accounting for the most relevant features of the experimental system. Some of the novel possibilities for electrocatalysis arising from far from equilibrium nonlinear processes in presence of autocatalysis are discussed.