WO₃ Nanoarray: An Efficient Electrochemical Oxygen Evolution Catalyst Electrode Operating in Alkaline Solution

It is fascinating to design and synthesize high-efficiency and noble-metal-free alkaline oxygen evolution reaction (OER) electrocatalysts. In this Communication, we describe the one-step hydrothermal synthesis of a WO 3 nanoarray directly grown on conductive carbon cloth (WO 3 /CC) for efficient water oxidation in 1.0 M KOH. As a monolithically integrated array catalyst, WO 3 /CC exhibits superior OER activity demanding overpotential as low as 280 mV to afford a benchmarking catalytic current density of 10 mA cm –2 . It is worth noting that WO 3 /CC also possesses strong electrochemical durability with 95% Faradaic yields.