Direct propylene epoxidation with oxygen using a photo-electro-heterogeneous catalytic system

Propylene oxide is a crucial feedstock in the plastic industry. The direct epoxidation of propylene using O 2 is considered among the most promising means of producing propylene oxide. Here we report an integrated photo-electro-heterogeneous catalytic system for propylene epoxidation with O 2 . Bismuth vanadate (or TiO 2 ) photocatalyst and a Co-based electrocatalyst produces H 2 O 2 . A titanium silicalite-1 heterogeneous catalyst subsequently epoxidizes propylene to propylene oxide with the in situ-generated H 2 O 2 . The proposed system enables propylene oxide production with O 2 as the sole oxidizing agent under light irradiation without using H 2 , a sacrificial agent, or external bias. It stably produces propylene oxide for 24 h with high selectivity (≥98%) under ambient conditions. These results demonstrate the potential of this catalytic system to produce chemical compounds in an environmentally benign manner.