Dual-site cooperation mediated by synergy in Mg-Co bimetallic oxide for high-performance styrene epoxidation reaction

Styrene epoxidation under mild reaction conditions is an important reaction to produce styrene oxide. Herein a synergistic intermetallic catalysis between Mg and Co in MgCo2O4 is revealed to be a facile strategy to facilitate the epoxidation performance, with the roles of Co-O and Mg-O sites in the O-Mg-O-Co-O structure responsible for activity and selectivity, respectively. Both experimental studies and theoretical calculations verify that the introduction of Mg into the Co3O4 framework contributes to the construction of alkaline environment on the catalyst surface, realizing a remarkable enhancement of the selectivity towards styrene oxide by suppressing its further transformation in a base-free condition. As a result, this strategy breaks the trade-off between activity and selectivity, contributing to both enhanced styrene conversion and selectivity to styrene oxide. The dual-site cooperation strategy in bimetallic oxides composed by earth-abundant elements is expected to provide important guidance and impetus for moving academically appealing chemistry such as styrene epoxidation to an industrial reality.