CuCo DAC used to change the hydrogenation sequence for efficient electrochemical C-N coupling

Abstract

Cu-based diatomic catalysts have been reported to selectively synthesize urea. However, problems such as high applied potential (–0.6 ∼ −1.5 V vs. RHE) and low urea yields are still being faced. In this article, we report a new class of CuCo diatomic catalyst (CuCo DAC) that exhibits high synthetic performance with a urea yield of 1.04 mol h−1 gCuCo−1 corresponding to a low applied potential (–0.45 V vs.RHE). This is the first reported molar level yield. In situ IR spectroscopy, TPD, H/D exchange experiment and DFT verified the effect of varying the hydrogenation sequence on urea properties. By optimizing the hydrogenation sequence of the reaction, an important nitrogen-containing intermediate (*NH2) for NO3- reduction is directly coupled with CO2RR intermediates to achieve efficient urea electrosynthesis. The direct coupling of *NH2 and *CO can effectively increase the chances of C-N coupling and lower the rate-determining step energy barrier.