Closing the carbon and nitrogen cycles by electrochemical methods using renewable energy to convert abundant or harmful feedstocks into high-value C- or N-containing chemicals has the potential to transform the global energy landscape. However, efficient conversion avenues have to date been mostly realized for the independent reduction of CO₂ or NO₃^–. The synthesis of more complex C–N compounds still suffers from low conversion efficiency due to the inability to find effective catalysts. To this end, here we present amorphous bismuth–tin oxide nanosheets, which effectively reduce the energy barrier of the catalytic reaction, facilitating efficient and highly selective urea production. With enhanced CO₂ adsorption and activation on the catalyst, a C–N coupling pathway based on *CO₂ rather than traditional *CO is realized. The optimized orbital symmetry of the C- (*CO₂) and N-containing (*NO₂) intermediates promotes a significant increase in the Faraday efficiency of urea production to an outstanding value of 78.36% at −0.4 V vs RHE. In parallel, the nitrogen and carbon selectivity for urea formation is also enhanced to 90.41% and 95.39%, respectively. The present results and insights provide a valuable reference for the further development of new catalysts for efficient synthesis of high-value C–N compounds from CO₂.

中文翻译：

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具有优化 C-N 耦合的非晶态铋-氧化锡纳米片，用于高效尿素合成

使用可再生能源通过电化学方法闭合碳和氮循环，将丰富或有害的原料转化为高价值的含碳或含氮化学品，有可能改变全球能源格局。然而，迄今为止，有效的转化途径大部分已实现用于独立还原CO ₂或NO ₃ ^–。由于无法找到有效的催化剂，更复杂的C-N化合物的合成仍然面临着转化效率较低的问题。为此，我们在此提出了非晶态氧化铋锡纳米片，它可以有效降低催化反应的能垒，促进高效、高选择性的尿素生产。通过增强催化剂上的CO _{2吸附和活化，实现了基于*CO 2}而不是传统*CO的C-N偶联途径。 C- (*CO ₂ ) 和含氮 (*NO _{2 ) 中间体的优化轨道对称性促进尿素生产的法拉第效率显着提高，在 -0.4 V} vs RHE下达到 78.36% 的出色值。与此同时，尿素形成的氮和碳选择性也分别提高至 90.41% 和 95.39%。目前的结果和见解为进一步开发用于从CO ₂高效合成高价值C-N化合物的新型催化剂提供了有价值的参考。