Mechanism of the electrochemical oxygen reduction on semiconductors

In collaboration with the atomistic modelling group, our interest is to provide crucial data on the nature of intermediates of the electrochemical oxygen reduction (ORR). Vibrational spectroscopy coupled to electrochemical experiments is able to show reaction pathways of the ORR. As opposed to noble metal, our interest in in the ORR on semiconductors. On the model system germanium, ATR-IR spectroscopy shows upright oriented superoxide and peroxide as intermediates. Details have been compiled by Ulrich Biedermann. Differences of the role of peroxide is found between acidic and alkaline electrolytes. A semiquantitative analysis of the linear dichroism permits a determination of the orientation of the intermediates, as well as the extraction of a quantity proportional to surface coverage.

Publications:

•Simantini Nayak, P. Ulrich Biedermann, Martin Stratmann, Andreas Erbe: In situ infrared spectroscopic investigation of intermediates in the electrochemical oxygen reduction on n-Ge(100) in alkaline perchlorate and chloride electrolyte. Electrochimica Acta, 106, 472-482 (2013).

•Simantini Nayak, P. Ulrich Biedermann, Martin Stratmann, Andreas Erbe: A Mechanistic Study of the Electrochemical Oxygen Reduction on the Model Semiconductor n-Ge(100) by ATR-IR and DFT. Physical Chemistry Chemical Physics, 15, 5771-5781 (2013).