Promoting Ethylene Selectivity from CO Electroreduction on CuO Supported onto CO Capture Materials.

Cu is a unique catalyst for CO electroreduction, since it can catalyze CO reduction to a series of hydrocarbons, alcohols, and carboxylic acids. Nevertheless, such Cu catalysts suffer from poor selectivity. High pressure of CO is considered to facilitate the activity and selectivity of CO reduction. Herein, a new strategy is presented for CO reduction with improved C H selectivity on a Cu catalyst by using CO capture materials as the support at ambient pressure. N-doped carbon (N C) was synthesized through high-temperature carbonization of melamine and l-lysine. We observed that the CO uptake capacity of N C depends on both the microporous area and the content of pyridinic N species, which can be controlled by the carbonization temperature (600-800 °C). The as-prepared CuO/N C catalysts exhibit a considerably higher C H faradaic efficiency (36 %) than CuO supported on XC-72 carbon black (19 %), or unsupported CuO (20 %). Moreover, there is a good linear relationship between the C H faradaic efficiency and CO uptake capacity of the supports for CuO. The local high CO concentration near Cu catalysts, created by CO capture materials, was proposed to increase the coverage of CO intermediate, which is favorable for the coupling of two CO units in the formation of C H . This study demonstrates that pairing Cu catalysts with CO capture supports is a promising approach for designing highly effective CO reduction electrocatalysts.