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

Abstract

An efficient heterogeneous copper-loaded catalytic system for photocatalytic hydrogen evolution and reduction of CO 2 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 CO 2 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 CO 2 under ambient conditions.