Hydrogen evolution reaction (HER) was studied over a rough rotating disk palladium electrode in 0.1 M sulfuric acid using steady-state polarization current measurements and electrochemical impedance spectroscopy (EIS). Among all the applied potentials, up to -0.074 V, two semicircles were found on the complex plane plots, which were attributed to the HER. Surface roughness factor, R-f = 23, was determined from the double-layer capacitance. The Tafel slope was -0.097 V dec(-1) and the value of the intrinsic exchange current density was 0.22 mA cm(-2). The double layer capacitance, charge transfer resistance, adsorption resistance, and pseudocapacitance as functions of potential were also determined from the EIS results. The HER proceeds through the Volmer-Heyrovslcy mechanism. (C) 2016 Elsevier B.V. All rights reserved.