Abstract: | The development of technologically viable electrodes for the electrochemical oxygen evolution reaction (OER) is a major bottleneck in chemical energy conversion. This article describes a facile one‐step hydrothermal route to deposit microcrystals of a robust Dexter–Silverton polyoxometalate oxygen evolution catalyst, Co6.8Ni1.2W12O42(OH)4(H2O)8], on a commercial nickel foam electrode. The electrode shows efficient and sustained electrochemical oxygen evolution at low overpotentials (360 mV at 10 mA cm?2 against RHE, Tafel slope 126 mV dec?1, faradaic efficiency (96±5) %) in alkaline aqueous solution (pH 13). Post‐catalytic analyses show no mechanical or chemical degradation and no physical detachment of the microcrystals. The results provide a blueprint for the stable “wiring” of POM catalysts to commercial metal foam substrates, thus giving access to technologically relevant composite OER electrodes. |