AuCu nanofibers for electrosynthesis of urea from carbon dioxide and nitrite

Gaseous CO2 Coupling with N-Containing Intermediates for Key C–N Bond Formation during Urea Production from Coelectrolysis over Cu

“…CO 2 + N 1 follows the Eley−Rideal mechanism, where the surface-bound N 1 species couples with incoming gaseous CO 2 to form C−N − to urea by Shao and co-workers (using Te-doped Pd nanocrystals as the catalyst), 22 Zheng and co-workers (using Cu-doped anatase TiO 2 as the catalyst), 23 and Wang and coworkers (using AuCu nanofibers as the catalysts). 27 The same pathway has been proposed by Zhang and co-workers in the coreduction of CO 2 + NO to urea catalyzed by Zn nanobelts. − catalyzed by cobalt βtetraaminophthalocyanine supported on carbon nanotubes by Wu et al 35 Interestingly, in the coreduction of CO 2 + NO 3 − to urea catalyzed by indium oxyhydroxide or hydroxide, Yu and co-workers have proposed that C−N formation may primarily occur through *CO 2 + *NO 2 .…”

“…Other C–N formation routes have been proposed in recent experimental studies using noncopper catalysts. *CO + *NH 2 has been suggested to be important in the coreduction of CO 2 + NO 2 – to urea by Shao and co-workers (using Te-doped Pd nanocrystals as the catalyst), Zheng and co-workers (using Cu-doped anatase TiO 2 as the catalyst), and Wang and co-workers (using AuCu nanofibers as the catalysts) . The same pathway has been proposed by Zhang and co-workers in the coreduction of CO 2 + NO to urea catalyzed by Zn nanobelts .…”

“…Several coelectrolysis systems are known to generate C–N-containing molecules, such as urea ((NH 2 ) 2 CO), − amines, − and amides. , Coreduction of CO 2 and NO 3 – /NO 2 – can produce urea. This type of catalytic reaction was first reported by Shibata et al more than two decades ago − and has recently regained the interest of scientists. − Urea can also be generated through the coreduction of CO 2 and N 2 , which has been reported by Kayan et al, Wang et al, and Zhang et al − By choosing the appropriate catalysts, Wang and co-workers have been able to coreduce CO 2 and NO 3 – to methylamine or ethylamine instead of urea. , Jiao and co-workers have discovered that under very basic conditions, rather than under the weakly acidic to near-neutral conditions used in the aforementioned C–N formation systems, the coreduction of CO and NH 3 on copper led to acetamide …”

Tuning the Coordination Structure of CuNC Single Atom Catalysts for Simultaneous Electrochemical Reduction of CO2 and NO3– to Urea

“…[4] Metal-based catalysts that have been investigated for urea production have exhibited activity for CO 2 RR to CO, indicating that a high CO 2 reduction capability is imperative for synthesizing urea. [11,51,52] On the basis of the above experimental results and DFT calculations, it is clear that the Cu-GS catalysts exhibit catalytic activity for these reactions and therefore present the potential for catalyzing CO 2 and NO 3 to urea. We test this hypothesis through carrying out both CO 2 RR and NO 3 RR.…”

“…[7,8] As a more cost-effective transition metal, Cu has been found to exhibit activity for these energy conversion reactions. [9,10] For example, AuCu nanofibers, [11] Cu-doped TiO 2 , [12] and metallic Cu [13] have been investigated for urea production; however, the individual electroreduction of CO 2 and NO x strongly competes with the desired C-N coupling reaction required for a high selectivity of urea, leading to the generation of byproducts such as CO, HCOOH, and NH 4…”