Using Cavity Microelectrodes for Electrochemical Noise Studies of Oxygen-Evolving Catalysts

被引：15

作者：

Rincon, Rosalba A. ^{[1
]}

Battistel, Alberto ^{[1
]}

Ventosa, Edgar ^{[1
]}

Chen, Xingxing ^{[1
,2
]}

Nebel, Michaela ^{[3
]}

Schuhmann, Wolfgang ^{[1
]}

机构：

[1] Ruhr Univ Bochum, CES, D-44780 Bochum, Germany

[2] Univ Sci & Technol Liaoning, Sch Chem Engn, Anshan 114051, Peoples R China

[3] Sensolytics GmbH, D-44799 Bochum, Germany

来源：

CHEMSUSCHEM | 2015年 / 8卷 / 03期

关键词：

cavity microelectrodes; electrochemistry; gas-evolving electrodes; oxygen; perovskite phases; WATER OXIDATION; ELECTRODES; EVOLUTION; POWDER; ELECTROCATALYSTS; PERFORMANCE; BUBBLES; BI2O3;

D O I：

10.1002/cssc.201402855

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Cavity microelectrodes were used as a binder-free platform to evaluate oxygen evolution reaction (OER) electrocatalysts with respect to gas bubble formation and departure. Electrochemical noise measurements were performed by using RuO2 as a benchmark catalyst and the perovskite La0.58Sr0.4Fe0.8Co0.2O3 as a non-noble metal OER catalyst with lower intrinsic conductivity. Changes in the current during the OER originate from variations in electrolyte resistance during the formation of the gas phase and partial coverage of the active area. Fluctuations observed in current and conductance transients were used to establish the contribution from the ohmic overpotential and to determine the characteristic frequency of oxygen evolution. The proposed quantitative determination of gas bubble growth and departure opens up the route for a rational interface design by considering gas bubble growth and departure as a main contributing factor to the overall electrocatalytic activity at high current densities.

引用

页码：560 / 566

页数：7

共 22 条

[1] Analysis and mitigation of the artefacts in electrochemical impedance spectroscopy due to three-electrode geometry [J].