South Korean and British researchers have jointly developed a new catalyst that can replace an expensive platinum catalyst in mass-production of hydrogen.
Ulsan National Institute of Science and Technology (UNIST) announced on Sept. 15 that its research team led by Professors Jeong Hu-young and Shin Hyeon-suk jointly developed the new catalyst with the research team led by Manish Chhowalla, a professor of the University of Cambridge in the United Kingdom.
The new catalyst is made by mixing chalcogenide, a new structure of metallic transition metals, and niobium sulfide (NbS). Chemical vapor deposition (CVD) is used in the synthesis process. The catalyst has realized 100 times higher current density than the existing two-dimensional transition metal, chalcogenide. The higher the current density, the amount of hydrogen produced in the same electric pressure increases.
The research team led by Jeong and Shin said, “In fact, an area of 1 square centimeter released 30 liters of hydrogen per hour when NbS is applied to the cathode of electrolytic cells which generate hydrogen. It is the similar figure with the commercialized platinum catalyst. The new catalyst has a high possibility of commercialization as it can mass produce hydrogen while replacing an expensive catalyst made of precious metals.
The latest study also analyzed the crystal structure of the synthesis catalyst through a cross section of scanning transmission electron microscope (STEM) method. As a result, atoms of niobium were additionally found in the layer of multi layered NbS. The additional atoms made a catalyst metallic. Jeong said, “When metallicity of the catalyst improves, hydrogen adsorption energy gets weaker. With the weaker adsorption energy, hydrogen atoms can more easily cling to the surface of the catalyst. It activates hydrogen generation response so it makes better catalyst.”
The latest study was conducted as part of the Future Material Discovery Material Program run by the National Research Foundation of Korea. The findings were published in the international journal Nature Materials on Aug. 27.