Heterogeneous Thermo And Electro Catalysis Over Single Atom Catalysts

To meet ever-growing energy demands while transitioning towards a more sustainable energy economy, novel materials are required. Single-atom catalysts have emerged as promising materials that offer to maximize atomic efficiency while also offering unique chemical advantages over their conventional nanoparticle counterparts. Despite notable successes since they were first discovered in 2010, many challenges still face these novel materials before they may become a commercially viable alternative to conventional catalysts. Although recent advancements in characterization techniques and synthesis methods have greatly accelerated the advancement of these materials, the atomic nature of single atoms sites prohibits detailed understanding of these materials. To help unravel the mysteries of these materials, computational models have emerged as a critical component for understanding these materials and guiding catalyst design. In this dissertation, we utilize first-principles calculations in conjunction with mean-field microkinetic modeling to elucidate atomic-scale insights into single-atom catalysts. These investigations include material screening to identify supporting materials that can stabilize high-density single atoms at catalytically relevant conditions, detailed mechanistic studies to elucidate active site structures under complex electrochemical environments, and identifying structural and chemical properties to tailor the catalytic performance of single-atom catalysts. Throughout this work, we seek to bridge the nanoscale properties derived from atomistic models with macroscopic observables obtained in experiments. To do this, we strive to develop comprehensive reaction networks while being cognizant of coverage effects from reaction intermediates and the reaction environment. Importantly, we also utilize microkinetic modeling to facilitate direct comparisons between theory and experiments. These principles enable us to deliver accurate computational predictions for guiding the rational design and discovery of novel materials for catalytic applications.