Metal carbide catalysts are essential to many widely used chemical processes. Fischer‐Tropsch synthesis, methane dehydroaromatization and biomass conversion catalysts are typically prepared in situ from a metal oxide precursor with a carbon‐containing gas. The reduction process of the metal oxide affects the final catalyst, as does the carburization gas mixture and metal promoters. By looking at materials that are carburized in situ, new insights can be gained about catalyst activation, fuel processing, and deactivation stages. The main focuses of this Review are iron carbide, molybdenum carbide and nickel carbide; analyzing catalyst synthesis methods, reduction steps, in situ carburization and improvements to the native processes. By combining years of research on these catalysts, trends and similarities are observed that can be used to improve current catalytic studies.

We report platinum catalysts for the efficient aerobic oxidation of olefins to form epoxides and/or derived glycol monoethers. The catalystsdiaqua and dichloro Pt II complexes supported by the ligand di(2-pyridine)methanesulfonate (dpms)are most active when they are covalently tethered to mesoporous silica nanoparticles (MSNs). Supporting the molecular Pt complexes on the MSNs prevents bimolecular catalyst deactivation. Using this strategy, >40 000 turnovers are achieved for the aerobic oxidation of norbornene in 2,2,2-trifluoroethanol. The position of the tether and the nature of other ligands in the metal coordination sphere (aqua, hydroxo, or chloro) are shown to affect the catalyst activity. The new MSN-supported Pt materials were characterized by nuclear magnetic resonance (NMR) spectroscopy, nitrogen physisorption, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA).

Tandem catalysis research has recently come alive with various methods to design biosynthetic pathways utilizing enzymes and inorganic catalysts in single-pot systems. Clever applications of porous supports have brought about ways for the successful integration of incompatible enzymes and inorganic catalysts into these onepot systems to enhance the properties of the combined catalysts. Over the past several years research in this area has shown that supports can be used to stabilize catalysts as well as act as active components within the systems. In this Perspective, we present and discuss current reports that demonstrate successful combinations of enzymes and inorganic catalysts supported on porous supports for tandem reactions and challenges yet to be overcome.

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