(273c) Metallic Co ALD Catalysts for Fuels from Syngas
Direct deposition of a metallic Co by ALD has been demonstrated using low-cost cobaltocene precursor and H2; this catalyst preparation method eliminates reduction of oxide and improves catalytic productivity. Eliminating high-temperature treatment of catalyst avoids sintering and incorporation of metal into the support (aluminate). Two methods of depositing metallic Co are discussed: on Al2O3and on W ALD. Both surfaces have exhibited deposition of metallic Co; however, the deposition reactions are vastly different.
Application of the Co catalyst deposited by metallic ALD has multiple advantages. First, cobaltocene is a less-expensive reactant than other proposed chemistries for metallic Co ALD. Second, metallic Co ALD will be less likely to sinter than incipient wetness catalysts because reduction temperatures are avoided. Third, the deposition of metallic Co compared to Co3O4 ALD provides higher productivity of Co catalyst because the metal does not form a mixed oxide with the support.