Oxygen Evolution Activity on Mo Added Zr Oxide Catalyst in Alkaline Solution

Abstract

In order to development of alternative anode of alkaline water electrolysis, we have focused on Zr oxide-based catalyst and investigated the activity of oxygen evolution reaction (OER) on Mo added Zr oxide-based catalyst in 7 M KOH at 30 oC. Mo added Zr oxide-based catalyst on Ti rod was prepared by the arc plasma deposition (APD) and R.F. sputtering. Compared with Mo-Zr binary oxide-based electrode (Mo-ZrOx) fabricating by the sputtering procedure, the MoO3 by APD on ZrOx by sputtering (MoO3/ZrOx) with TaOx by sputtering as an interlayer showed higher OER activity, and it reached over 1 mA cm-2 of OER geometric current density at 1.8 V vs. RHE. The Tafel slope of OER on MoO3/ZrOx was 81 mV dec-1 while that on Mo-ZrOx was over 200 mV dec-1. According to results from electrochemical impedance spectroscopy, the charge transfer resistance of MoO3/ZrOx was much smaller than that of Mo-ZrOx.