Preparation of several novel Salen-Co(III) visible photocatalysts and their application in the copolymerization of carbon dioxide with propylene oxide

Carbon dioxide (CO2) is a renewable carbon source, which can be copolymerized with epoxide to prepare aliphatic polycarbonate and cyclic carbonate. In this paper, a series of novel SalenCo(III) photocatalysts were synthesized for the first time, and the copolymerization of CO2 and propylene oxide (PO) was stud-ied. The effects of reaction conditions on catalytic activity and selectivity were investigated. The results show that the catalyst 3 with strong polarity Schiff base and planar conjugated dye has the highest ac-tivity and selectivity for CO2 and PO photocopolymerization among the four SalenCo(III) photocatalysts. Due to the synergistic action of the catalyst and Mn4Ca nanocluster, the ring-opening of PO is promoted and the photocatalytic efficiency is greatly improved. The introduction of visible light improves the cat-alytic efficiency, and increasing light intensity can better improve the catalytic efficiency. The optimal copolymerization condition was 60 degrees C, 6 h, 200 W, 2 MPa of CO2 with Mn4Ca nanocluster/catalyst 3.(c) 2023 Elsevier B.V. All rights reserved.