An oxygen-coordinated cobalt single-atom electrocatalyst boosting urea and urea peroxide production

Abstract

Urea and urea peroxide play important role in agricultural and industrial production. The development of mild and efficient synthetic methods to achieve these two chemicals has aroused great attention, but...

Electrochemical urea production using carbon dioxide and nitrate: state of the art and perspectives

“…18 Remarkably, to date, to our best knowledge, only a scant few studies (around 21) have been published in the past three years related to urea electrosynthesis starting from NO 3 − and CO 2 . 29–52 These manuscripts provide a solid starting point for the research, but fundamental investigations are needed to clarify the steps that determine the most activity and selectivity: no direct experimental evidence has yet been reported showing the formation of intermediate species, but many DFT studies suggest that that pathway is energetically favourable for the formation of urea, at least on some electrocatalytic structures. For example Sargent et al showed by DFT calculation that the pathway seems to be favoured on Zn, rather than on Cu, in a ZnCu electrocatalyst.…”

“…39 On the other hand, an oxygen-coordinated cobalt single-atom electrocatalyst (Co–O–C) achieved a urea yield rate of 2704.2 ± 183.9 mg h −1 mg cat −1 due to reliable interactions between neighboring Co–(O–C 2 ) 4 sites promoted the C–N coupling for urea electrosynthesis. 46 Moreover, atomically dispersed nitrogen-coordinated single transition metal sites ( e.g. , Cu–N x –C) 35,37,60 (Fig.…”

Co-doped MnS/NiS/Ni3S2 grown in situ on hydrophilic nickel foam for energy-efficient urea-assisted alkaline hydrogen production

“…5–7 Thus, to overcome this limitation, sacrificial agent oxidation reactions (SAORs) have been proposed as alternatives to OER. 8,9 Among them, urea oxidation reaction (UOR, CO(NH 2 ) 2 + 6OH − → N 2 + 5H 2 O + CO 2 + 6e − ) with a low theoretical potential of 0.37 V versus the reversible hydrogen electrode (RHE) is one of the ideal replacements, enabling a theoretical energy saving of ≈70%. 10–15 In addition, the use of urea-containing wastewater in UOR further demonstrates its significance.…”