Experimental Aspects in Benchmarking of the Electrocatalytic Activity

Abstract

With the high interest in improving the performance of electrocatalysts for technologically significant reactions, great efforts are directed at the assessment of the activities of various catalytic materials. For this purpose, it is important to compare the catalytic activities measured using different methods and under different conditions. To achieve this, it is of utmost importance to avoid certain methodological and instrumental issues that can severely affect the obtained experimental results. Using well‐defined systems, we demonstrate the importance of experimental conditions in the assessment and benchmarking of the activity of catalytic processes for various reactions. Particularly, we demonstrate that the correction of the uncompensated ohmic resistance using impedance spectroscopy measurements requires particular attention and additional procedures which are normally ignored. Additionally, we demonstrate how the uncompensated resistance changes with the potential if a non‐conducting gas phase is accumulated in the system, hence influencing the activity measurement. It is further shown that a correct choice for surface‐limited reactions for the determination of the real surface area of catalytic electrodes plays a key role in ensuring more meaningful activity assessment.

Toward an Active and Stable Catalyst for Oxygen Evolution in Acidic Media: Ti‐Stabilized MnO2

“…The data are presented using the RHE scale and corrected for Ohmic losses, measured with EIS in the range of 1-200 000 Hz at a DC potential of 10 mV. [ 90 ] The Ohmic drop for the RDE tests was in the order of 30-40 Ω and for the EQCM tests was in the order of 20-25 Ω.…”

Carbon catalysts for electrochemical hydrogen peroxide production in acidic media

“…CV was conducted in a potential range 0- fitting of the impedance spectra was done according to the procedure described in ref [63].…”

Acetaldehyde as an Intermediate in the Electroreduction of Carbon Monoxide to Ethanol on Oxide‐Derived Copper

“…85 %o ft he uncompensated ohmic drop was correctedf or in the software,a sm easured through electrochemical impedance spectroscopy. [25] If significant, the remaining 15 %was corrected for after the experiment. Theo hmic drop typically ranged from 20 to 50 W, depending on the WE position relative to the RE.…”