Journal article

Publication year: 2019

Pages: 6530-6539

Journal: ACS Catalysis

Volume number: 9

Issue number: 7

ISSN: 2155-5435

Open access status: Green

DOI Link: https://doi.org/10.1021/acscatal.9b01402

Publisher: American Chemical Society

Abstract: 
Sophisticated IrO2(110)-based model electrodes are prepared by deposition of a 10 nm thick single-crystalline IrO2(110) layer supported on a structure-directing RuO2(110)/Ru(0001) template, exposing a regular array of mesoscopic rooflike structures. With this model electrode together with the dedicated in situ synchrotron based techniques (SXRD, XRR) and ex situ characterization techniques (SEM, ToF-SIMS, XPS), the corrosion process of IrO2(110) in an acidic environment (pH 0.4) is studied on different length scales. Potential-induced pitting corrosion starts at 1.48 V vs SHE and is initiated at so-called surface grain boundaries, where three rotational domains of IrO2(110) meet. The most surprising result is, however, that even when the electrode potential is increased to 1.94 V vs SHE 60-70% of the IrO2 film still stays intact down to the mesoscale and atomic scale and no uniform thinning of the IrO2(110) layer is encountered. Neither flat IrO2(110) terraces nor single steps are attacked. Ultrathin single crystalline IrO2(110) layers seem to be much more stable to anodic corrosion than hitherto expected.

Harvard Citation style: Weber, T., Pfrommer, J., Abb, M., Herd, B., Khalid, O., Rohnke, M., et al. (2019) Potential-Induced Pitting Corrosion of an IrO2(110)-RuO2(110)/Ru(0001) Model Electrode under Oxygen Evolution Reaction Conditions, ACS Catalysis, 9(7), pp. 6530-6539. https://doi.org/10.1021/acscatal.9b01402

APA Citation style: Weber, T., Pfrommer, J., Abb, M., Herd, B., Khalid, O., Rohnke, M., Lakner, P., Evertsson, J., Volkov, S., Bertram, F., Znaiguia, R., Carla, F., Vonk, V., Lundgren, E., Stierle, A., & Over, H. (2019). Potential-Induced Pitting Corrosion of an IrO2(110)-RuO2(110)/Ru(0001) Model Electrode under Oxygen Evolution Reaction Conditions. ACS Catalysis. 9(7), 6530-6539. https://doi.org/10.1021/acscatal.9b01402