The Impact of Mn addition on Ta Oxide-Based Electrocatalysts for Oxygen Evolution Reaction in Acid

Abstract

In order to develop non-platinum group metals anode electrocatalyst for the proton exchange membrane water electrolysis, the catalytic activity of Ta oxide-based electrocatalyst with and without Mn addition for the oxygen evolution reaction (OER) have been investigated. The Ta oxide-based electrocatalyst with Mn addition (Mn-TaOx) has greatly increased current density than that without any addition. From XPS spectra, the Mn-TaOx after electrochemical measurement did not detect the peak identified Mn oxides while the sample before electrochemical measurement showed clearly the peak that identified Mn oxides. From the slow scan voltammogram of Mn-TaOx, the redox peak of Mn species was detected. Since the electric charge of redox peak and the OER current density has linear relation in Mn-TaOx, the Mn content which is below the detection limit of XPS is affected on the enhancement of OER activity at Ta oxide-based electrocatalyst.

(Digital Presentation) Oxygen Evolution Reaction on Non-Precious Metal Oxide-Based Electrocatalysts With and Without Low Potential Scan in Acidic Solution

“…To enhance the OER activity of Ta oxide-based electrocatalyst, we focused and investigated the Mn addition because it is reported 14 that the γ-MnO2 has significant OER activity and it also has high stability in solution at a pH of 2. From our past results, Ta oxide-based electrocatalyst with Mn addition showed higher OER activity than that without addition 15 , but its activity was very far from conventional materials. In this study, we have prepared Ta oxide-based electrocatalyst with Mn addition and have enhanced its OER activity with and without low potential scan in acidic solution.…”