Selective CO2-to-Formate Conversion Driven by Visible Light over a Precious-Metal-Free Nonporous Coordination Polymer

Metal-organic frameworks (MOFs) and coordination polymers (CPs) are potential candidates for high-performance photocatalysts because of their high tunability of electronic and structural properties. For example, MOFs and CPs having a high specific surface area (similar to 1000 m(2) g(-1)) have been applied as visible-light-driven photocatalysts for CO2 reduction and water splitting. Herein, we show a unique CP possessing a metal-sulfur bond with Pb2+, an earth-abundant metal ion. Different from ordinary high-surface-area MOFs and CPs, this CP is nonporous and has just 0.7 m(2) g(-1) surface area. Nevertheless, owing to its capability of absorbing visible light up to & SIM;500 nm, it efficiently photocatalyzes CO2 reduction to formate (HCOO-) under visible -light irradiation with > 99% selectivity and an apparent quantum yield of 2.6% at 400 nm, even without postmodification treatment such as cocatalyst loading. These values are the highest yet reported for a precious-metal-free single-component photocatalyst for the visible-light-driven reduction of CO2 to HCOO-. This work may thus shed light on the great potential of nonporous CPs as building units of photocatalytic CO2 conversion systems.

Automated summary

Metal-organic frameworks and coordination polymers are promising candidates for high-performance photocatalysts due to their tunable electronic and structural properties. This study presents a unique coordination polymer with a metal-sulfur bond, exhibiting efficient photocatalytic reduction of CO2 to formate under visible light irradiation.