Design of a Four-Atom Cluster Embedded in Carbon Nitride for Electrocatalytic Generation of Multi-Carbon Products

The development of efficient and stable catalysts for the electrocatalytic CO2 and CO reduction reactions (CORR) is under active investigation, but the problems of poor selectivity and low efficiency for C-2 products still exist. We design a two-dimensional carbon nitride material (C5N2H2) that contains an eight N-atom structure capable of coordinating four-metal atom clusters and supporting simultaneously two carbon oxide molecules needed for the C-2 coupling. The designed material has excellent electrical conductivity and stability. After high-throughput screening of catalytic performance of multiple four-metal clusters embedded into the framework, we systematically investigate the CORR process of 11 candidates. We find that Cu4-C5N2H2 has superior selectivity and low limiting potential for generating ethylene, while Cu2Zn2-C5N2H2 is selective and efficient to synthesize ethanol. Further, we discover a novel type of descriptor related to 2D material flexibility to evaluate the potential-determining step for generating ethylene. Our report both broadens the possibilities for few-atom CO reduction and demonstrates a novel substrate flexibility-related descriptor to predict the catalytic performance of materials.

Automated summary

Researchers have designed a two-dimensional carbon nitride material with excellent conductivity and stability, which supports the electrocatalytic CO2 reduction reaction. After screening multiple metal clusters, Cu4-C5N2H2 showed superior selectivity and low limiting potential for generating ethylene, while Cu2Zn2-C5N2H2 exhibited selectivity and efficiency for synthesizing ethanol. In addition, a novel descriptor related to the flexibility of 2D materials was discovered to evaluate the potential-determining step for generating ethylene. This study expands the possibilities for few-atom CO reduction and introduces a new substrate flexibility-related descriptor to predict catalytic performance.