Molecular catalysis science: Nanoparticle synthesis and instrument development for studies under reaction conditions

The synthesis of architecturally designed catalytic nanostructures and their in situ characterization under reaction conditions enable the development of catalysts with improved stability, reactivity, and product selectivity. Throughout this review paper, we will explore three recent reports that demonstrate the invaluable synergetic impact of combining synthesis, catalysis, and in situ spectroscopy for catalysts development. In the first example, product selectivity in 1,3 butadiene hydrogenation reaction was tuned by employing size-selected Pt nanoparticles as catalysts. SFG vibrational spectroscopy measurements uncovered the mechanism that induced the size-dependent selectivity. The important role of metal/metal-oxide interface during CO oxidation reaction is demonstrated in the second part of this review paper. In situ synchrotron-sourced X-ray spectroscopy correlated between the oxidation state of the metal-oxide support and its impact on the catalytic reactivity of supported Pt nanoparticles. In the third example, dendrimer-encapsulated Au nanoparticles were used as catalyst for cascade reactions, which were previously catalyzed by homogeneous catalysts. Reactants into product evolution and the oxidation state of catalytically active Au nanoparticles within the flow reactor were mapped with micrometer-sized IR and X-ray beams. These three examples demonstrate the important role of colloidal synthesis and in situ spectroscopy measurements for in-depth analysis of structure-reactivity correlations.