Multipolar donor-acceptor (D-A) hypercrosslinked polymers provide well-defined charge-transfer pathways that enable efficient and selective CO2 photoreduction under visible light. While such systems hold promise for CO2 conversion, achieving high activity, long-term stability, and product selectivity remains challenging. Here, we present HCP-CoTPP-Cz-1, a multipolar D-A hypercrosslinked conjugated polymer synthesized via Scholl coupling. HCP-CoTPP-Cz-1 exhibits a high CO2 adsorption capacity of 9.71 wt% at 273 K, which is associated with cobalt-containing units incorporated within the polymer network. In addition, the extended π-conjugated D-A framework promotes efficient charge separation and charge-carrier transport. Under photocatalytic conditions employing Ru(bpy)3Cl2 as the photosensitizer and triethanolamine as the hole-sacrificial agent, HCP-CoTPP-Cz-1 achieves a CO evolution rate of 4402.5 µmol g-1 h-1 with an apparent quantum yield of 0.51% at 450 nm, representing a 37.5% enhancement compared with the non-D-A polymer HCP-CoTPP-s. Both catalysts maintain CO selectivity >99%. Mechanistic studies reveal that the multipolar D-A architecture facilitates charge separation and transfer, suppresses electron-hole recombination, and enhances both CO2 capture capacity and catalytic stability. By demonstrating a rational polymer design that enables efficient and stable CO2 photoreduction, this work presents a feasible strategy to convert CO2 into CO within green chemical production pathways.
Ullah et al. (Fri,) studied this question.