Synthesis of molybdenum carbide thin films for producti̇on of hydrogen via electrochemical water splitting

In this study, wet-chemical techniques were used to synthesize colloidal molybdenum nanoparticles (NPs). The synthesis of colloidal Molybdenum NPs was done by using pyrolysis of hexacarbonyl Molybdenum in 1-Octadecene under Argon atmosphere at 220 °C. Further, metallic Molybdenum and Molybdenum carbide catalysts were fabricated by spin coating of synthesized Molybdenum NPs onto graphite substrates and subsequent heat treatments at elevated temperatures under Argon atmosphere. For the first time, we achieved the fabrication of Molybdenum carbide thin films on graphite substrate from colloidal Molybdenum NPs without utilizing any reducing gas. In addition, Platinum NPs were synthesized by pyrolysis of platinum-bis(acetylacetonate) precursor and following subsequent heat treatments on graphite substrates. Prepared Platinum-based electrodes were used as a reference material towards hydrogen evolution reaction. Characterization of molybdenum, platinum and molybdenum carbide catalysts were carried out by using X-Ray Diffractometer, Transmission Electron Microscope, and Scanning Electron Microscope. Linear sweep voltammetry, cyclic voltammetry, chronoamperometry/chronopotentiometry and electrochemical impedance spectroscopy measurements were performed in a three-electrode cell in 0,5 molar sulfuric acid aqueous electrolyte solution (pH = 0). Molybdenum carbide thin films exhibit excellent catalytic activity and chemical stability for hydrogen evolution reactions.