In this work, the H
2 dissociation and acetylene hydrogenation on Cu doped CeO
2(111) were studied using density functional theory calculations. The results indicated that Cu doping promotes the formation of oxygen vacancy (O
v) which creates Cu/O and Ce/O
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In this work, the H
2 dissociation and acetylene hydrogenation on Cu doped CeO
2(111) were studied using density functional theory calculations. The results indicated that Cu doping promotes the formation of oxygen vacancy (O
v) which creates Cu/O and Ce/O frustrated Lewis pairs (FLPs). With the help of Cu/O FLP, H
2 dissociation can firstly proceed via a heterolytic mechanism to produce Cu-H and O-H by overcoming a barrier of 0.40 eV. The H on Cu can facilely migrate to a nearby oxygen to form another O-H species with a barrier of 0.43 eV. The rate-determining barrier is lower than that for homolytic dissociation of H
2 which produces two O-H species. C
2H
2 hydrogenation can proceed with a rate-determining barrier of 1.00 eV at the presence of Cu-H and O-H species., While C
2H
2 can be catalyzed by two O-H groups with a rate-determining barrier of 1.06 eV, which is significantly lower than that (2.86 eV) of C
2H
2 hydrogenated by O-H groups on the bare CeO
2(111), showing the high activity of Cu doped CeO
2(111) for acetylene hydrogenation. In addition, the rate-determining barrier of C
2H
4 further hydrogenated by two O-H groups is 1.53 eV, much higher than its desorption energy (0.72 eV), suggesting the high selectivity of Cu doped CeO
2(111) for C
2H
2 partial hydrogenation. This provides new insights to develop effective hydrogenation catalysts based on metal oxide.
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