Tadashi Ogitsu is a deputy group leader of Quantum Simulation Group at Lawrence Livermore National Laboratory and is the point of contact for DOE/EERE HydroGEN consortium, which is designed to facilitate sustainable hydrogen production R&D.
Recent progresses in theory of catalytic reactions led to successful computationally guided discoveries of novel catalyst systems. However, simultaneously, it also disclosed presence of intimate relation between energetics and kinetic of elemental catalytic reaction processes for multi-step catalytic reactions such as oxygen evolution, CO2 reduction, ammonia synthesis, a part of which has been known as Evans-Polanyi relation. Presence of such a relation suggests that catalytic system consisting of a homogeneous and a single component catalyst material will likely to face a great challenge in improving catalytic performance compared to known conventional catalysts since substituting the catalyst material in hope of improving kinetics of rate limiting step will likely to lead to a worse kinetics of the other steps, one of which may turn into the rate limiting step. This relation also poses a challenge in controlling selectivity since the kinetics of branching reactions are also likely to be correlated in a linear fashion. At the presentation, we will first discuss about underlying concepts based on our research experiences about computational design of novel catalyst [Choi et al. JCPC 117, 21772 (2013); Choi et al. Adv. Ener. Matt. 1501423 (2015)] as well as about transport properties of reaction intermediate at solid-liquid interfaces [Wood et al. JACS 135, 15774 (2013)]. We will then discuss about the factors that need to be further studied in order to overcome the challenge implied by the scaling relation. This work was performed under the auspices of the U.S. Department of Energy under contract No. DE-AC52-07NA27344, and supported by DOE Fuel Cell Technology Office.
Audience Take away:
• Basics of catalytic reaction processes
• The known obstacles for novel catalyst development
• I would like to share what I have leaned about the success and the limitation in computationally aided novel catalyst design and further discuss candidate approaches that may lead to a solution for overcoming the known obstacles.