Abstract: Ammonia and hydrogen are both highly important chemicals used for the production of fertilizers and/or the storage of energy. For ammonia production, the Haber-Bosch process is an energy-intensive and polluting method; therefore, there is great interest in developing catalysts for thermochemical production of ammonia at comparatively lower pressures and temperatures. For hydrogen production, pyrolysis allows for natural gas to be the source of hydrogen while not emitting any carbon dioxide. Molten metal reactors suffer from low activation energies and have therefore not been industrialized yet. Here, we exploit the nature of bi- and trai-metallic phase diagrams to design a catalyst for both systems. Exsolution of heterogeneously structured tri-metallic Ru-Cu-Fe nanoparticles from lanthanum ferrate were found to catalyze thermochemical ammonia synthesis at atmospheric pressure (0.1 MPa) at a record-breaking 7.54 mmol/gcat/h. Copper, which is not active for ammonia synthesis, was shown to be a promoter by preventing agglomeration, producing additional oxygen vacancies in the support which act as nitrogen activation sites. For hydrogen, we exploit the dual-phase portion of the Ni-Sn and Ni-Bi phase diagrams to lower the activation energy of conventional molten-metal methane pyrolysis, whereby doubling the hydrogen production rate and being able to continuously separate graphitic carbon.
Short Biography: Brian Rosen is the Vice Dean for International Affairs in the Faculty of Engineering at Tel Aviv University, an Associate Professor the Department of Materials Science and Engineering, and the head of the Energy Materials Laboratory. The laboratory specializes in the design of novel ceramic catalyst for fuel cells (PEMFC, AFC, H2/NH3-SOFC), and synthetic fuel production (H2, NH3, syngas) via thermochemical and electrochemical routes. The Rosen lab investigates ways to modulate catalyst activity by tuning the metal-ceramic interface via multi-scale defect engineering, strain engineering, solid-state phase separations, and electronic structure modulation. Prof. Rosen was named as U.S. Department of Energy Office of Science Graduate Fellow in 2010. His work was the basis for a US-based startup company, Dioxide Materials (Boca Raton, FL) which develops industrial CO2 electrolyzers and the Israeli startup Fonto Power (acquired by Solar Edge) which develops SOFC-Battery hybrid systems. Professor Rosen was given the Young Innovator Award in Nanocatalysis Research by the Springer journal Nano Research in 2021, and the Climate Solutions Breakthrough Research Prize in 2023. Prof. Rosen received his PhD in Chemical Engineering from the University of Illinois at Urbana-Champaign in 2013 under the advisement of Rich Masel and Paul Kenis.
