Spin-dependent electrochemical kinetics at a semiconducting photocathode

We present experimental evidence that the electrochemical rate at a semiconducting photocathode can be affected by the relative spin orientations of the electrons in the semiconductor and of the redox species in the electrolyte. Here the spin orientations are acted upon independently by combination of a large magnetic field and optical pumping of the photoelectrons with circularly polarized light. The effect can be qualitatively understood in terms of the classical models for electrochemical transfer at a semiconducting photoelectrode. The results show that the spin polarization may not be drastically affected upon the electrochemical transfer and may provide a probe for the electrochemical interface.