Modulation of -Block Electron Orbits in Metal-Organic Frameworks for CO Capture and Electrochemical Reduction.

Developing catalysts with excellent CO capture capability and electrochemical CO reduction reaction (CORR) at a wide potential range simultaneously is significant but remains a formidable challenge. Here, two novel InMg defective trinuclear cluster-based MOFs (SNNU-41 and SNNU-42) with abundant -block unsaturated coordinated sites were reported and exhibited good CO capture and CORR performance simultaneously. Due to the suitable micropores, SNNU-41 showed higher CO capture ability at different adsorption pressure conditions. On account of the rigid framework and the closer band center to Fermi level, SNNU-42 accelerated the conversion of CO molecule to C1 efficiency. Notably, via adjusting the ratio of -block metal (In) in the SNNU-42 framework, the performance of the CORR was promoted drastically. SNNU-42 with the InMg (1:1.8) mixed cluster delivered an excellent Faradaic efficiency of 91.3% for C1 products and high selectivity of 72.0% for HCOOH at -2.5 V (vs Ag/Ag) with a total current density of 77.2 mA cm. This work provides a possibility for efficient CO capture and CORR electrocatalysts through the modulation of electronic structures and composition in MOFs.