Theoretical studies of acrolein hydrogenation on Au20 nanoparticle

Abstract

Goldnanoparticles play a key role in catalytic processes. We investigated the kinetics of stepwise hydrogenation of acrolein on Au 20 cluster model and compared with that on Au(110) surface. The rate-limiting step barrier of C  C reduction is about 0.5 eV higher than that of C  O hydrogenation on Au(110) surface. On Au 20 nanoparticle, however, the energy barrier of the rate-determining step for C  C hydrogenation turns out to be slightly lower than the value for the C  O reduction. The selectivity difference on the two substrate models are attributed to different adsorption modes of acrolein: via the C  C on Au 20 , compared to through both C  C and C  O on Au(110). The preference switch implies that the predicted selectivity of competitive hydrogenation depends on substrate model sensitively, and particles with more low-coordinated Au atoms than flat surfaces are favorable for C  C hydrogenation, which is in agreement with experimental result.