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

• Published in: ACS catalysis Vol. 12; no. 16; pp. 10172 - 10178
• Main Authors: Kamakura, Yoshinobu, Yasuda, Shuhei, Hosokawa, Naoki, Nishioka, Shunta, Hongo, Sawa, Yokoi, Toshiyuki, Tanaka, Daisuke, Maeda, Kazuhiko
• Format: Journal Article
• Language: English
• Published: American Chemical Society 19.08.2022
• Subjects: artificial photosynthesis; CO2 reduction; visible-light response; metal−organic frameworks; earth-abundant metal
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.2c02177

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 (∼1000 m2 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 m2 g–1 surface area. Nevertheless, owing to its capability of absorbing visible light up to ∼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.