A Simple Electrochemical Approach Based on Inexpensive Wall-Jet Screen-Printed Ring Disk Electrode to Evaluate Oxygen Reduction Catalysts

A simple electrochemical approach to evaluate oxygen reduction catalysts using an inexpensive screen‐printed ring disk carbon electrode system, consisting of a ring electrode deposited with MnO2 and a disk electrode modified with the catalysts for study, is developed in this study. The as‐prepared MnO2 is selective and sensitive for H2O2 oxidation in the presence of O2 and is crucial to the proposed approach. By coupling with a wall‐jet electrochemical cell, the product generated from the reduction reaction at the disk electrode can effectively be monitored at the MnO2‐deposited ring electrode. Model catalysts of nano‐Au and nano‐Pd representing 2e− reduction of O2 to H2O2 and 4e− reduction to H2O, respectively, were evaluated as electrode materials in oxygen reduction reaction to demonstrate the applicability of the proposed method.