MOF-derived AgCo alloy nanoparticle protected by mesoporous carbon as chemoselective catalyst for hydrogenation of citral

Abstract

A new robust AgCo alloy catalyst which presents as clean uniform bimetallic nanoparticles (NPs) protected by a mesoporous carbon layer was feasibly produced from a controllable pyrolysis strategy of metal-organic frameworks (MOFs) precursor. The pyrolysis destroyed the microporous structure of Ag(I)-doped Co-MOF but generated a new mesoporous carbon layer, which led to effective substrates diffusion and in situ reduction and generation of the highly active alloy nanoparticles. Benefited from the well dispersed bimetallic alloy NPs and the interaction with Ag and Co, which can adjust the electron distribution on the catalyst surface, the as-prepared AgCo alloy catalyst delivered remarkably selective hydrogenation activity of citral with nearly full conversion and 70% selectivity for hydrogenation of citral to nerol and geraniol under the optimum reaction conditions, which is comparable to the reported Pt, Ru and Re catalysts. In addition, since the AgCo alloy NPs were well protected from aggregation and leaching by the mesoporous carbon, the magnetic catalyst exhibited extremely high catalytic recyclability without any decrease of conversion and selectivity after ten cycles of reuse.