Highly Efficient Ir-CoO x Hybrid Nanostructures for the Selective Hydrogenation of Furfural to Furfuryl Alcohol.

Decoration of noble metals with transition-metal oxides has been intensively studied for heterogeneous catalysis. However, controllable syntheses of metal-metal oxide heterostructures are difficult, and elucidation of such interfaces is still challenging. In this work, supported IrCo alloy nanoparticles are transformed into supported Ir-CoO _x close-contact nanostructures by in situ calcination and following selective reduction. Relative to Ir/Al ₂ O ₃ , Ir-CoO _x /Al ₂ O ₃ shows greatly enhanced activities for the hydrogenation of furfural derivatives to the corresponding furfuryl alcohol derivatives with more than 99% selectivity and demonstrates significantly improved activities and selectivity for hydrogenations of α,β-unsaturated aldehydes to α,β-unsaturated alcohols. The modification of Ir surfaces with CoO _x prevents Ir nanoparticles from growing, achieving high thermal and catalytic stabilities. Theoretic calculation suggests that the better catalytic performance of Ir-CoO _x /Al ₂ O ₃ is ascribed to the Ir-CoO _x interaction, which promotes the absorption of furfural as well as desorption of furfuryl alcohol, resulting in enhanced catalytic activities.