The widespread development of technologies for green hydrogen production strictly relies on the availability of durable electrocatalysts that can operate in either acidic or alkaline electrolytes while using a limited amount of platinum group metals. In this work, we present an effective strategy based on electrodeposition as a low-cost method to obtain low-loading Ru catalysts on carbon electrodes for the hydrogen evolution reaction in an acidic environment. The deposition conditions have been investigated and optimized in order to have uniform coverage, a large number of active sites, and good electrocatalytic performance. The morphology and chemical structure have been investigated using scanning electron microscopy and X-ray photoelectron spectroscopy measurements. Excellent catalytic activity has been achieved with a Ru loading of 0.06 mg cm–2, obtaining an overpotential of 67 mV at 10 mA cm–2 and …