Utility of a Copper-Embedded Porous Organic Polymer for Visible-Light-Triggered Green Hydrogen Production and CO2 Reduction

An efficient heterogeneous copper-loaded catalytic system for photocatalytic hydrogen evolution and reduction of CO2 to methanol has been reported. For the present photocatalytic reaction, an elegant strategy has been developed to heterogenize the homogeneously active copper-based catalysts via immobilization on the porphyrin-based porous organic polymer (namely, TpTph or TpPOP). This heterogeneous system acts as a very effective catalyst for visible-light-triggered hydrogen production (a high hydrogen production yield of about 598 μmol) and selective CO2 reduction to methanol (a high yield of about 1.8 mol/gcat upon exposure to 15 W white light-emitting diode) under sustainable conditions (room temperature, atmospheric pressure, cocatalyst-free). Notably, Cu@TpPOP offers much easier recyclability than the homogeneous one. Further, the detailed theoretical (DFT) and experimental studies unravel mechanistic pathways to convergent photocatalytic hydrogen evolution and selective photoreduction of CO2 under ambient conditions.