电催化二氧化碳和硝酸根合成尿素研究进展

doi:10.11949/0438-1157.20251045

摘要/Abstract

摘要：

电催化CO₂和NO₃^-偶联合成尿素被认为是一种清洁可持续的绿色生产途径，有助于碳中和和人工氮循环。然而，因其反应复杂、反应物吸附慢、副反应竞争等多方面因素，导致电催化合成尿素面临法拉第效率低、尿素选择性差、难以满足工业需求等问题。本文综述了电催化CO₂和NO₃^-合成尿素的研究进展，深入讨论了C-N耦联的反应机理，分析总结了催化剂性能提升策略，包括尺寸调控、晶面调控、空位工程等催化剂设计策略以及H型槽、流动池、MEA（膜电极组件）等反应器设计方法。最后，提出了该领域未来的研究以及工业化应用所面临的挑战与展望。

关键词: 尿素合成, 电化学, C-N偶联, 催化剂, 反应器设计, 二氧化碳

Abstract:

Electrocatalytic CO₂ and NO₃^- coupling synthesis of urea is a clean and sustainable green production pathway, which is conducive to carbon neutralization and artificial nitrogen cycle. However, due to its complex reaction, slow adsorption of reactants, side reaction competition and other factors, the electrocatalytic synthesis of urea faces problems such as low Faraday efficiency, poor urea selectivity, and difficulty in meeting industrial needs. In this paper, the research progress of electrocatalytic CO₂ and NO₃^- synthesis of urea is reviewed. The reaction mechanism of C-N coupling is discussed in depth. The strategies for improving catalyst performance are analyzed and summarized, including catalyst design strategies such as size control, crystal plane control and vacancy engineering, and reactor design methods such as H-groove, flow cell and MEA (Membrane Electrode Assembly). Finally, the challenges and prospects of future research and industrial applications in this field are proposed.

Key words: urea synthesis, electrochemistry, C-N coupling, catalyst, reactor design, carbon dioxide

车志凯, 张谭, 宋芋茹, 李晋平, 刘光. 电催化二氧化碳和硝酸根合成尿素研究进展[J]. 化工学报, DOI: 10.11949/0438-1157.20251045.

Zhikai CHE, Tan ZHANG, Yuru SONG, Jinping LI, Guang LIU. Research progress in electrocatalytic synthesis of urea from carbon dioxide and nitrate[J]. CIESC Journal, DOI: 10.11949/0438-1157.20251045.

图/表 11

参考文献 74

[1]	He F, Tong S R, Luo Z Y, et al. Accelerating net-zero carbon emissions by electrochemical reduction of carbon dioxide[J]. Journal of Energy Chemistry, 2023, 79: 398-409.
[2]	Zhang S R, Bai X Y, Zhao C W, et al. China's carbon budget inventory from 1997 to 2017 and its challenges to achieving carbon neutral strategies[J]. Journal of Cleaner Production, 2022, 347: 130966.
[3]	Zhang Z Z, Li S J, Zhang Z, et al. A review on electrocatalytic CO₂ conversion via C–C and C–N coupling[J]. Carbon Energy, 2024, 6(2): e513.
[4]	Wan Y C, Zheng M Y, Yan W, et al. Fundamentals and rational design of heterogeneous C-N coupling electrocatalysts for urea synthesis at ambient conditions[J]. Advanced Energy Materials, 2024, 14(28): 2303588.
[5]	Wang C, Gao W Q, Hu W, et al. Recent advances in electrochemical synthesis of urea via C–N coupling[J]. Journal of Energy Chemistry, 2024, 98: 294-310.
[6]	Lim J, Fernández C A, Lee S W, et al. Ammonia and nitric acid demands for fertilizer use in 2050[J]. ACS Energy Letters, 2021, 6(10): 3676-3685.
[7]	Gruber N, Galloway J N. An Earth-system perspective of the global nitrogen cycle[J]. Nature, 2008, 451(7176): 293-296.
[8]	Liu S, Yang H B, Su X, et al. Rational design of carbon-based metal-free catalysts for electrochemical carbon dioxide reduction: a review[J]. Journal of Energy Chemistry, 2019, 36: 95-105.
[9]	Luo Y T, Xie K, Ou P F, et al. Selective electrochemical synthesis of urea from nitrate and CO₂ via relay catalysis on hybrid catalysts[J]. Nature Catalysis, 2023, 6(10): 939-948.
[10]	Jiang M H, Zhu M F, Wang M J, et al. Review on electrocatalytic coreduction of carbon dioxide and nitrogenous species for urea synthesis[J]. ACS Nano, 2023, 17(4): 3209-3224.
[11]	Kohlhaas Y, Tschauder Y S, Plischka W, et al. Electrochemical urea synthesis[J]. Joule, 2024, 8(6): 1579-1600.
[12]	Zhu X R, Zhou X C, Jing Y, et al. Electrochemical synthesis of urea on MBenes[J]. Nature Communications, 2021, 12: 4080.
[13]	Ma L J, Yuan J L, Liu Z T, et al. Mesoporous electrocatalysts with p–n heterojunctions for efficient electroreduction of CO₂ and N₂ to urea[J]. ACS Applied Materials & Interfaces, 2024, 16(20): 26015-26024.
[14]	Yu Y D, Lv Z, Liu Z Y, et al. Activation of Ga liquid catalyst with continuously exposed active sites for electrocatalytic C-N coupling[J]. Angewandte Chemie International Edition, 2024, 63(18): e202402236.
[15]	Hu Q, Zhou W L, Qi S, et al. Pulsed co-electrolysis of carbon dioxide and nitrate for sustainable urea synthesis[J]. Nature Sustainability, 2024, 7(4): 442-451.
[16]	Jiao Y R, Li H B, Jiao Y, et al. Activity and selectivity roadmap for C–N electro-coupling on MXenes[J]. Journal of the American Chemical Society, 2023, 145(28): 15572-15580.
[17]	Ying Y R, Fan K, Qiao J L, et al. Rational design of atomic site catalysts for electrocatalytic nitrogen reduction reaction: one step closer to optimum activity and selectivity[J]. Electrochemical Energy Reviews, 2022, 5(3): 6.
[18]	Liu X, Jiao Y, Zheng Y, et al. Mechanism of C-N bonds formation in electrocatalytic urea production revealed by ab initio molecular dynamics simulation[J]. Nature Communications, 2022, 13: 5471.
[19]	Wei X X, Liu S Q, Liu H J, et al. Lattice oxygen-driven co-adsorption of carbon dioxide and nitrate on copper: a pathway to efficient urea electrosynthesis[J]. Journal of the American Chemical Society, 2025, 147(7): 6049-6057.
[20]	Li J Y, Li Y F, Li L S, et al. Remote carbon monoxide spillover improves tandem urea electrosynthesis[J]. Angewandte Chemie International Edition, 2025, 64(10): e202421266.
[21]	Meng N N, Ma X M, Wang C H, et al. Oxide-derived core–shell Cu@Zn nanowires for urea electrosynthesis from carbon dioxide and nitrate in water[J]. ACS Nano, 2022, 16(6): 9095-9104.
[22]	Wang Y, Xia S, Zhang J F, et al. Spatial management of CO diffusion on tandem electrode promotes NH2 intermediate formation for efficient urea electrosynthesis[J]. ACS Energy Letters, 2023, 8(8): 3373-3380.
[23]	Chen S B, Hai G T, Cheng H, et al. Efficient urea electrosynthesis via coordination of the reaction rate of carbon dioxide and nitrate co-reduction[J]. AIChE Journal, 2024, 70(10): e18515.
[24]	Fu J J, Yang Y, Hu J S. Dual-sites tandem catalysts for C–N bond formation via electrocatalytic coupling of CO₂ and nitrogenous small molecules[J]. ACS Materials Letters, 2021, 3(10): 1468-1476.
[25]	Zhang S B, Geng J, Zhao Z, et al. High-efficiency electrosynthesis of urea over bacterial cellulose regulated Pd–Cu bimetallic catalyst[J]. EES Catalysis, 2023, 1(1): 45-53.
[26]	Gao W T, Wu Q Y, Fan X F, et al. Promoting electrocatalytic reduction of CO₂ and nitrate to urea on N-doped porous hollow carbon spheres[J]. ACS Applied Materials & Interfaces, 2024, 16(38): 50726-50735.
[27]	Zhao J M, Yuan Y, Zhao F, et al. Identifying the facet-dependent active sites of Cu₂O for selective C-N coupling toward electrocatalytic urea synthesis[J]. Applied Catalysis B: Environmental, 2024, 340: 123265.
[28]	Xu M Q, Wu F F, Zhang Y, et al. Kinetically matched C–N coupling toward efficient urea electrosynthesis enabled on copper single-atom alloy[J]. Nature Communications, 2023, 14: 6994.
[29]	Geng J, Ji S H, Jin M, et al. Ambient electrosynthesis of urea with nitrate and carbon dioxide over iron-based dual-sites[J]. Angewandte Chemie International Edition, 2023, 62(6): e202210958.
[30]	Zhang C, Zhou Q, Li Z Y, et al. Promoting the intermediates hydrogenation for urea electrosynthesis over an "active hydrogen pump" catalyst[J]. Angewandte Chemie International Edition, 2025, 64(29): e202507869.
[31]	Song X N, Jin X Y, Chen T H, et al. Boosting urea electrosynthesis via asymmetric oxygen vacancies in Zn-doped Fe₂O₃ catalysts[J]. Angewandte Chemie International Edition, 2025, 64(28): e202501830.
[32]	Wei X X, Liu Y Y, Zhu X R, et al. Dynamic reconstitution between copper single atoms and clusters for electrocatalytic urea synthesis[J]. Advanced Materials, 2023, 35(18): 2300020.
[33]	Zhao Y L, Ding Y X, Li W L, et al. Efficient urea electrosynthesis from carbon dioxide and nitrate via alternating Cu–W bimetallic C–N coupling sites[J]. Nature Communications, 2023, 14: 4491.
[34]	Li Y, Zheng S S, Liu H, et al. Sequential co-reduction of nitrate and carbon dioxide enables selective urea electrosynthesis[J]. Nature Communications, 2024, 15: 176.
[35]	Hu B H, Lu R H, Wang W L, et al. Directing the C–N coupling pathway enables efficient urea electrosynthesis[J]. Journal of the American Chemical Society, 2025, 147(25): 21764-21777.
[36]	Huang X M, Li Y F, Xie S J, et al. The tandem nitrate and CO₂ reduction for urea electrosynthesis: role of surface N-intermediates in CO₂ capture and activation[J]. Angewandte Chemie International Edition, 2024, 63(24): e202403980.
[37]	Ma X Y, Mao B G, Yu Z Q, et al. Elucidating relay catalysis on copper clusters with satellite single atoms for enhanced urea electrosynthesis[J]. Angewandte Chemie International Edition, 2025, 64(19): e202423706.
[38]	Zhao Q L, Lu X X, Wang Y N, et al. Sustainable and high-rate electrosynthesis of nitrogen fertilizer[J]. Angewandte Chemie International Edition, 2023, 62(33): e202307123.
[39]	Wang Y, Xia S, Cai R, et al. Dynamic reconstruction of two-dimensional defective Bi nanosheets for efficient electrocatalytic urea synthesis[J]. Angewandte Chemie International Edition, 2024, 63(16): e202318589.
[40]	Yang Y D, Wu G Z, Jiang J D, et al. Stabilization of Cu^δ+ sites within MnO₂ for superior urea electro-synthesis[J]. Advanced Materials, 2024, 36(41): 2409697.
[41]	Zhang T B, Wang P, Yang C, et al. Sub-2 nm Cu and co codoping SnO₂ ultrathin nanosheet with mesoporous structure for efficient electrocatalytic urea synthesis[J]. Journal of the American Chemical Society, 2025, 147(36): 33108-33119.
[42]	Lv C D, Zhong L X, Liu H J, et al. Selective electrocatalytic synthesis of urea with nitrate and carbon dioxide[J]. Nature Sustainability, 2021, 4(10): 868-876.
[43]	Li Z Y, Zhou P, Zhou M, et al. Synergistic electrocatalysis of crystal facet and O-vacancy for enhancive urea synthesis from nitrate and CO₂ [J]. Applied Catalysis B: Environmental, 2023, 338: 122962.
[44]	Wu Q, Dai C C, Meng F X, et al. Potential and electric double-layer effect in electrocatalytic urea synthesis[J]. Nature Communications, 2024, 15: 1095.
[45]	Huang R, Xue F, Wang P F, et al. Multi-orbital electronic coupling mediated by integrating multiple-metal hybridizations at ultrafast heating accumulation for efficient electrochemical urea synthesis[J]. Journal of Energy Chemistry, 2025, 103: 657-664.
[46]	Liang J Y, Deng S J, Li Z Y, et al. Spin state modulation with oxygen vacancy orientates C/N intermediates for urea electrosynthesis of ultrahigh efficiency[J]. Advanced Materials, 2025, 37(9): 2418828.
[47]	Lv C D, Lee C, Zhong L X, et al. A defect engineered electrocatalyst that promotes high-efficiency urea synthesis under ambient conditions[J]. ACS Nano, 2022, 16(5): 8213-8222.
[48]	Zhang Y, Li Z H, Chen K, et al. Promoting electroreduction of CO₂ and NO₃ ^- to urea via tandem catalysis of Zn single atoms and In₂O_3-x [J]. Advanced Energy Materials, 2024, 14(47): 2402309.
[49]	Wan Y Y, Zhang Z Y, Qian J M, et al. Single-atom Rh₁ alloyed co for urea electrosynthesis from CO₂ and NO₃ ^– [J]. Nano Letters, 2024, 24(35): 10928-10935.
[50]	Xiang J Q, Qiang C F, Shang S Y, et al. Relay catalysis of isolated rhodium-alloyed copper boosts urea electrosynthesis from nitrate and CO₂ [J]. ACS Nano, 2024, 18(43): 29856-29863.
[51]	Chen C, Li S, Zhu X R, et al. Balancing sub-reaction activity to boost electrocatalytic urea synthesis using a metal-free electrocatalyst[J]. Carbon Energy, 2023, 5(10): e345.
[52]	Liu X W, Kumar P V, Chen Q, et al. Carbon nanotubes with fluorine-rich surface as metal-free electrocatalyst for effective synthesis of urea from nitrate and CO₂ [J]. Applied Catalysis B: Environmental, 2022, 316: 121618.
[53]	Ye W, Zhang Y, Chen L, et al. A strongly coupled metal/hydroxide heterostructure cascades carbon dioxide and nitrate reduction reactions toward efficient urea electrosynthesis[J]. Angewandte Chemie International Edition, 2024, 63(48): e202410105.
[54]	Song X N, Ma X D, Chen T H, et al. Urea synthesis via coelectrolysis of CO₂ and nitrate over heterostructured Cu–Bi catalysts[J]. Journal of the American Chemical Society, 2024, 146(37): 25813-25823.
[55]	Yin H Q, Sun Z S, Zhao Q P, et al. Electrochemical urea synthesis by co-reduction of CO₂ and nitrate with Fe^II-Fe^IIIOOH@BiVO₄ heterostructures[J]. Journal of Energy Chemistry, 2023, 84: 385-393.
[56]	Zhou M, Zhang Y, Li H, et al. Tailoring O-monodentate adsorption of CO₂ initiates C-N coupling for efficient urea electrosynthesis with ultrahigh carbon atom economy[J]. Angewandte Chemie International Edition, 2025, 64(2): e202414392.
[57]	Mao Y N, Jiang Y, Liu H, et al. Ambient electrocatalytic synthesis of urea by co-reduction of NO₃ ^- and CO₂ over graphene-supported In₂O₃ [J]. Chinese Chemical Letters, 2024, 35(3): 108540.
[58]	Du W Y, Sun Z Y, Chen K, et al. Synergistic Cu single atoms and MoS₂-edges for tandem electrocatalytic reduction of NO₃ ^- and CO₂ to urea[J]. Advanced Energy Materials, 2024, 14(43): 2401765.
[59]	Zhang Y, Li Z H, Qiang C F, et al. Atomically dispersed Cu on In₂O₃ for relay electrocatalytic conversion of nitrate and CO₂ to urea[J]. ACS Nano, 2024, 18(36): 25316-25324.
[60]	Zhan P, Zhuang J J, Yang S, et al. Efficient electrosynthesis of urea over single-atom alloy with electronic metal support interaction[J]. Angewandte Chemie International Edition, 2024, 63(33): e202409019.
[61]	Niu Z Z, Chi L P, Liu R, et al. Rigorous assessment of CO₂ electroreduction products in a flow cell[J]. Energy & Environmental Science, 2021, 14(8): 4169-4176.
[62]	Lin L, He X Y, Xie S J, et al. Electrocatalytic CO₂ conversion toward large-scale deployment[J]. Chinese Journal of Catalysis, 2023, 53: 1-7.
[63]	Ma W C, He X Y, Wang W, et al. Electrocatalytic reduction of CO₂ and CO to multi-carbon compounds over Cu-based catalysts[J]. Chemical Society Reviews, 2021, 50(23): 12897-12914.
[64]	Tu X J, Zhu X R, Bo S W, et al. A universal approach for sustainable urea synthesis via intermediate assembly at the electrode/electrolyte interface[J]. Angewandte Chemie International Edition, 2024, 63(3): e202317087.
[65]	Fu S Y, Chu K B, Guo M H, et al. Ultrasonic-assisted hydrothermal synthesis of RhCu alloy nanospheres for electrocatalytic urea production[J]. Chemical Communications, 2023, 59(29): 4344-4347.
[66]	Li Z W, Xu M Q, Wang J Q, et al. Boosting up electrosynthesis of urea with nitrate and carbon dioxide via synergistic effect of metallic iron cluster and single-atom[J]. Small, 2024, 20(38): 2400036.
[67]	Zhao C, Jin Y, Yuan J K, et al. Tailoring activation intermediates of CO₂ initiates C–N coupling for highly selective urea electrosynthesis[J]. Journal of the American Chemical Society, 2025, 147(10): 8871-8880.
[68]	Wan Y Y, Zhang Z Y, Wang X M, et al. Electrocatalytic urea production with nitrate and CO₂ on a Ru-dispersed co catalyst[J]. Advanced Functional Materials, 2024, 34(41): 2406438.
[69]	Li H, Xu L T, Bo S W, et al. Ligand engineering towards electrocatalytic urea synthesis on a molecular catalyst[J]. Nature Communications, 2024, 15: 8858.
[70]	Wang Y J, Zhu X R, An Q Z, et al. Electron deficiency is more important than conductivity in C-N coupling for electrocatalytic urea synthesis[J]. Angewandte Chemie International Edition, 2024, 63(49): e202410938.
[71]	Li M, Shi Q J, Li Z H, et al. Photoelectrocatalytic synthesis of urea from carbon dioxide and nitrate over a Cu₂O photocathode[J]. Angewandte Chemie International Edition, 2024, 63(33): e202406515.
[72]	Wei X X, Wen X J, Liu Y Y, et al. Oxygen vacancy-mediated selective C–N coupling toward electrocatalytic urea synthesis[J]. Journal of the American Chemical Society, 2022, 144(26): 11530-11535.
[73]	Anastasiadou D, Ligt B, He Y Y, et al. Carbon dioxide and nitrate co-electroreduction to urea on CuOxZnOy[J]. Communications Chemistry, 2023, 6: 199.
[74]	Dai Z C, Chen Y X, Zhang H K, et al. Surface engineering on bulk Cu₂O for efficient electrosynthesis of urea[J]. Nature Communications, 2025, 16: 3271.

	Bosch-Meiser 工艺	电催化合成尿素工艺
反应条件	高温、高压且需要大型、耐高压的抗腐蚀设备	常温常压，对设备要求低，安全性高
原料来源	高纯度NH₃和CO₂（NH₃来自高能耗的哈伯法合成氨，CO₂通常来自化石燃料重整或其它工业过程）	广泛且直接，N₂（直接来自空气）、CO₂（工业废气）、NO₃^-（工业废水）
环境影响	大（巨大的碳排放以及工业废水排放）	绿色合成（清洁无污染）
主要优点	1.技术可靠、工艺成熟2.高选择性和高收率3.强大的规模效应	1.反应条件温和，安全节能2.原料绿色，可直接利用N₂和废弃CO₂3.流程简单，易于模块化
主要缺点	1.高能耗、高碳排放，对环境不友好2.依赖化石燃料作为原料和能源3.集中式生产，基础设施要求高4.工艺复杂	1.技术不成熟，距离实用化遥远2.选择性/法拉第效率低3.产物分离困难，成本高昂4.催化剂的活性和稳定性不足

	Bosch-Meiser 工艺	电催化合成尿素工艺
反应条件	高温、高压且需要大型、耐高压的抗腐蚀设备	常温常压，对设备要求低，安全性高
原料来源	高纯度NH₃和CO₂（NH₃来自高能耗的哈伯法合成氨，CO₂通常来自化石燃料重整或其它工业过程）	广泛且直接，N₂（直接来自空气）、CO₂（工业废气）、NO₃^-（工业废水）
环境影响	大（巨大的碳排放以及工业废水排放）	绿色合成（清洁无污染）
主要优点	1.技术可靠、工艺成熟2.高选择性和高收率3.强大的规模效应	1.反应条件温和，安全节能2.原料绿色，可直接利用N₂和废弃CO₂3.流程简单，易于模块化
主要缺点	1.高能耗、高碳排放，对环境不友好2.依赖化石燃料作为原料和能源3.集中式生产，基础设施要求高4.工艺复杂	1.技术不成熟，距离实用化遥远2.选择性/法拉第效率低3.产物分离困难，成本高昂4.催化剂的活性和稳定性不足

催化剂	电解质	最佳电位	产率	法拉第效率	参考文献
W800-Cu	0.1 M KHCO₃+0.01 M KNO₃	-0.6 V vs. RHE	1373.5 µg h^-1 mg_cat^-1	12.8%	^[23]
Co₁-TiO₂	含 1.0 M K⁺ 的PBS和 KNO₃	-0.8 V vs. RHE	212.8 mmol h^-1 g^-1	36.2%	^[64]
RhCu	0.1M KNO₃	-0.6 V vs. RHE	26.81 mmol g^-1 h^-1	34.82%	^[65]
FeNC-Fe₁N₄/C	0.1 M KHCO₃+0.1 M KNO₃	—	38.2 mmol g_cat^-1 h^-1	66.5%	^[66]
Cu@Zn纳米线	0.2 M KHCO3+0.1 M KNO3	-1.02 V vs. RHE	7.29 μmol cm^-2 h^-1	9.28%	^[21]
RP-AuCu	0.1 M KHCO₃+0.1 M KNO₃	-0.6 V vs. RHE	22.9 mmol g_cat^-1 h^-1	88.5%	^[67]
Ru₁Co	0.1 M KHCO₃+0.1 M KNO₃	-0.5 V vs. RHE	22.34 mmol h^-1 g^-1	50.1%	^[68]
CuPc-Amino	0.1 M KHCO₃+0.05 M KNO₃	-1.6 V vs. RHE	103.1 mmol h^-1 g^-1	11.9%	^[69]
TiO₂-C	0.1M KNO₃	-0.9 V vs. RHE	43.37 mmol g^-1 h^-1	48.88%	^[36]
Cu/PI-500	0.1 M KHCO₃+0.1 M KNO₃	-1.4 V vs. RHE	255.0 mmol h^-1 g^-1	14.3%	^[70]
Cu₂O	0.1M KNO₃	-0.017 V vs. RHE	29.71 μmol g^-1 h^-1	12.9%	^[71]
Vo-CeO₂-750	0.1 M KHCO₃+0.05 M KNO₃	-1.6 V vs. RHE	943.6 mg h^-1 g^-1	—	^[72]
CuO₅₀ZnO₅₀	0.1 M Na₂SO₄+0.1 M NaNO₃	-0.8 V vs. RHE	—	41%	^[73]
h-Cu/Cu₂O MPs	0.5 M KHCO₃+0.05 M KNO₃	-0.3 V vs. RHE	632.1 µg h^-1 mg_cat^-1	43.2%	^[74]
CuWO₄	0.1M KNO₃	-0.2 V vs. RHE	98.5 µg h^-1 mg_cat^-1	70.1%	^[33]
OL-Cu	0.9 M KHCO₃+0.1 M KNO₃	-0.7 V vs. RHE	298.67 mmol h^-1 g^-1	28.64%	^[19]
Pd₂Au₁/RuO₂	1 M KOH+0.1 M KNO₃	-0.5 V vs. RHE	237.8 mmol g_cat^-1 h^-1	68.0%	^[20]

催化剂	电解质	最佳电位	产率	法拉第效率	参考文献
W800-Cu	0.1 M KHCO₃+0.01 M KNO₃	-0.6 V vs. RHE	1373.5 µg h^-1 mg_cat^-1	12.8%	^[23]
Co₁-TiO₂	含 1.0 M K⁺ 的PBS和 KNO₃	-0.8 V vs. RHE	212.8 mmol h^-1 g^-1	36.2%	^[64]
RhCu	0.1M KNO₃	-0.6 V vs. RHE	26.81 mmol g^-1 h^-1	34.82%	^[65]
FeNC-Fe₁N₄/C	0.1 M KHCO₃+0.1 M KNO₃	—	38.2 mmol g_cat^-1 h^-1	66.5%	^[66]
Cu@Zn纳米线	0.2 M KHCO3+0.1 M KNO3	-1.02 V vs. RHE	7.29 μmol cm^-2 h^-1	9.28%	^[21]
RP-AuCu	0.1 M KHCO₃+0.1 M KNO₃	-0.6 V vs. RHE	22.9 mmol g_cat^-1 h^-1	88.5%	^[67]
Ru₁Co	0.1 M KHCO₃+0.1 M KNO₃	-0.5 V vs. RHE	22.34 mmol h^-1 g^-1	50.1%	^[68]
CuPc-Amino	0.1 M KHCO₃+0.05 M KNO₃	-1.6 V vs. RHE	103.1 mmol h^-1 g^-1	11.9%	^[69]
TiO₂-C	0.1M KNO₃	-0.9 V vs. RHE	43.37 mmol g^-1 h^-1	48.88%	^[36]
Cu/PI-500	0.1 M KHCO₃+0.1 M KNO₃	-1.4 V vs. RHE	255.0 mmol h^-1 g^-1	14.3%	^[70]
Cu₂O	0.1M KNO₃	-0.017 V vs. RHE	29.71 μmol g^-1 h^-1	12.9%	^[71]
Vo-CeO₂-750	0.1 M KHCO₃+0.05 M KNO₃	-1.6 V vs. RHE	943.6 mg h^-1 g^-1	—	^[72]
CuO₅₀ZnO₅₀	0.1 M Na₂SO₄+0.1 M NaNO₃	-0.8 V vs. RHE	—	41%	^[73]
h-Cu/Cu₂O MPs	0.5 M KHCO₃+0.05 M KNO₃	-0.3 V vs. RHE	632.1 µg h^-1 mg_cat^-1	43.2%	^[74]
CuWO₄	0.1M KNO₃	-0.2 V vs. RHE	98.5 µg h^-1 mg_cat^-1	70.1%	^[33]
OL-Cu	0.9 M KHCO₃+0.1 M KNO₃	-0.7 V vs. RHE	298.67 mmol h^-1 g^-1	28.64%	^[19]
Pd₂Au₁/RuO₂	1 M KOH+0.1 M KNO₃	-0.5 V vs. RHE	237.8 mmol g_cat^-1 h^-1	68.0%	^[20]