Abstract:
Heterogeneous catalysts have largely been characterized as metal nanoparticles supported on relatively innocent or simple supports such as Al2O3, SiO2, carbon, and others. Hence, the catalyst/support repertoire has been somewhat limited over the past hundred years, despite the breadth of the field and increasing demands from society. Usually, heterogeneous catalysis is seen as a surface phenomenon. However, fine tuning of the bulk structure of a material can lead to unusual electronic effects and participation of lattice species in the catalytic cycle, leading to new catalysts with unique mechanisms.
As a solid state chemistry group, we focus on new hydrides,1–5 carbides/nitrides,6–8 intermetallics,9,10 mixed anion systems, and high-entropy materials11,12 for reactions and catalysis. We have previously identified that hydrides in solids are unusually exchangeable, leading to many applications in hydrogenation catalysis and inorganic material synthesis. Additionally, intermetallics, an extremely diverse group of materials, exhibit many unusual properties due to their electronic structure, especially in terms of work functions and valence electron counts. Together, these form an immense undertapped reserve of materials for new catalysts and potential new chemical transformations. We will present some recent results on these materials.
Biography
Yoji Kobayashi obtained his B.A. (Honors) in organometallic chemistry with David Glueck (Dartmouth College, USA), and in 2002 his PhD in inorganic materials with Thomas Mallouk (Penn State, USA). After postdoctoral work on metal organic frameworks with Jeffrey Long (UC Berkeley), he joined Kyoto University in 2010 as an Assistant Professor, and later Lecturer and Associate Professor. Since 2021, Yoji Kobayashi has been at KAUST, hosting his group in solid state chemistry and catalysis while also currently chairing the Chemistry Program at KAUST. His research focuses on various hydride/nitrides, intermetallics, high-entropy systems, and other oxides for catalysis and structural studies.
References
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2. Tang, Y. et al. Metal-Dependent Support Effects of Oxyhydride-Supported Ru, Fe, Co Catalysts for Ammonia Synthesis. Adv. Energy Mater. 1801772 (2018).
3. Tang, Y., Kobayashi, Y., Tassel, C., Yamamoto, T. & Kageyama, H. Hydride-Enhanced CO2 Methanation: Water-Stable BaTiO2.4H0.6 as a New Support. Adv. Energy Mater. 8, 1800800 (2018).
4. Kobayashi, Y. et al. Titanium-Based Hydrides as Heterogeneous Catalysts for Ammonia Synthesis. J. Am. Chem. Soc. 139, 18240–18246 (2017).
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