Cobalt molybdenum disulfide, (CoMoS2) catalysts are evaluated as active electrocatalysts for the production of hydrogen gas in acidic aqueous media. These highly-active hydrogen evolution reaction (HER) catalysts are obtained from pretreatment of ammonium tetrathiomolybdate (ATM) with different amines precursors, and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and their surface areas are determined by Brunauer-Emmett-Teller (BET) surface area analyses. Electrochemical studies indicate that these CoMoS2 materials exhibit enhanced catalytic performance for hydrogen gas production with overpotentials ranging from 0.127 to 0.144 V, which are significant less than CoMoS2 synthesized directly from ATM under the same synthetic techniques (0.173 V). These CoMoS2 catalysts are also stable in the presence of strong acidic media after a considerably long period of time (10 h) for maintaining their efficiencies for hydrogen gas evolution. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.