Selective oxidation of styrene on an oxygen-adsorbed Cu(111): a comparison with Au(111)

The reaction mechanism for the styrene selective oxidation on the oxygen preadsorbed Cu(111) surface has been studied by the density functional theory calculation with the periodic slab model. The calculated result indicated that the process includes two steps: forming the oxametallacycle intermediate (OMMS) and then producing the products. In addition, it was found that the second step, from OMMS to the product, is the rate-controlling step, which is similar to the previous work of ethylene selective oxidation. The present result indicated that the selectivity towards the formation of styrene epoxide on Cu(111) is much higher than that on Au(111). More importantly, we found that the mechanism via the OMMS (2) (i.e., the preadsorbed atomic oxygen bound to the CH(2) group involved in C(6)H(5)-CH=CH(2)) to produce styrene epoxide is kinetically favored than that of OMMS (1). We also found that the selectivity toward the styrene epoxide formation on Cu(2)O is similar to that of Cu(111).