Sequential co-reduction of nitrate and carbon dioxide enables selective urea electrosynthesis
Publication Name
Nature Communications
Abstract
Despite the recent achievements in urea electrosynthesis from co-reduction of nitrogen wastes (such as NO3−) and CO2, the product selectivity remains fairly mediocre due to the competing nature of the two parallel reduction reactions. Here we report a catalyst design that affords high selectivity to urea by sequentially reducing NO3− and CO2 at a dynamic catalytic centre, which not only alleviates the competition issue but also facilitates C−N coupling. We exemplify this strategy on a nitrogen-doped carbon catalyst, where a spontaneous switch between NO3− and CO2 reduction paths is enabled by reversible hydrogenation on the nitrogen functional groups. A high urea yield rate of 596.1 µg mg−1 h−1 with a promising Faradaic efficiency of 62% is obtained. These findings, rationalized by in situ spectroscopic techniques and theoretical calculations, are rooted in the proton-involved dynamic catalyst evolution that mitigates overwhelming reduction of reactants and thereby minimizes the formation of side products.
Open Access Status
This publication may be available as open access
Volume
15
Issue
1
Article Number
176
Funding Number
2023NSFSC0434
Funding Sponsor
Sichuan Province Science and Technology Support Program