Enhanced stability of cobalt catalysts by atomic layer deposition for aqueous-phase reactions

Abstract

A thin atomic layer deposition (ALD) TiO₂ coating successfully stabilizes cobalt particles supported on TiO₂ for aqueous-phase hydrogenation (APH) reactions by preventing leaching and sintering of cobalt. The uncoated conventional cobalt catalysts leach under the same conditions. Using Al₂O₃ coating of Co/γ-Al₂O₃ causes the formation of an irreducible cobalt aluminate phase which has no catalytic activity. The ALD TiO₂ decorated cobalt catalyst is active for APH of a range of feedstocks including furfuryl alcohol, furfural, and xylose whereas classic non-ALD cobalt catalysts have very low activity for these reactions.