Electronic structure modulation of metallic Co via N-doped carbon shell and Cu-doping for enhanced semi-hydrogenation of phenylacetylene to styrene

Abstract

Styrene, an important monomer in the production of polystyrene, is usually mixed with a small number of phenylacetylene which readily causes the poisoning of catalyst during styrene polymerization. To address this issue, we reported a nitrogen-doped carbon encapsulated CuCo bimetallic catalyst (CuxCo@NC) for styrene production from phenylacetylene semi-hydrogenation. The CuxCo@NC catalyst obtained a 100% conversion of phenylacetylene along with a high 94.6% selectivity of styrene, far higher than those of single metal Co@C and Co@NC catalysts. Detailed characterizations unveiled that the CuxCo@NC catalyst fabricated by a dual-regulation strategy showed Mott-Schottky effect, in which the electrons transferred from metallic Cu to Co and then to outer N-doped carbon shells. Moreover, the electron transfers of metallic Co could be regulated by Mott-Schottky effect with which to improve the semi-hydrogenation of phenylacetylene to styrene. This work provides an feasible pathway to effectively design the supported metal catalysts for highly selective semi-hydrogenation of alkynes to alkenes.