Citation: Huihua GONG, Tianhua CUI, Li JI, Liyuan ZHANG, Xueli ZHENG, Haiyan FU, Hua CHEN, Jiawei MAO, Ruixiang LI. Efficient hydrogenation of CO₂ realized by Ru-NNN complex[J]. Chinese Journal of Inorganic Chemistry, ;2026, 42(5): 1085-1095. doi: 10.11862/CJIC.20250321 shu

Efficient hydrogenation of CO₂ realized by Ru-NNN complex

Huihua GONG ^{1, 2, #} ,
Tianhua CUI ^{3, #} ,
Li JI ⁴ ,
Liyuan ZHANG ¹ ,
Xueli ZHENG ² ,
Haiyan FU ² ,
Hua CHEN ² ,
Jiawei MAO ^{5, 6,,} ,
Ruixiang LI ^2,,

1.
Special Agricultural Resources in Tuojiang River Basin Sharing and Service Platform of Sichuan Province, Analytical and Testing Center, College of Chemistry and Environmental Engineering, Neijiang Normal University, Neijiang, Sichuan 641112, China
2.
Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
3.
Shaanxi Hydrogen Energy Research Institute Co., Ltd., Xi′an 712046, China
4.
Sichuan Research Institute of Chemical Quality and Safety Testing, Chengdu 610031, China
5.
Sichuan Institute of Product Quality Supervision and Inspection, Chengdu 610100, China
6.
Key Laboratory of Vehicle Fuel Quality Safety and Risk Assessment, State Administration for Market Regulation, Chengdu 610100, China

Corresponding author: Jiawei MAO, 147608837@qq.com Ruixiang LI, liruixiang@scu.edu.cn
Received Date: 20 October 2025
Revised Date: 29 January 2026

Figures(6)

To develop highly stable and active Ru complex catalysts for CO₂ hydrogenation, we synthesized Ru complexes bearing rigid pincer-type tridentate NNN (pyrazole-pyridine-pyrazole) ligands and weakly coordinated triphenylphosphine (PPh₃) ligands. The NNN ligands can strongly chelate with the Ru metal center, contributing to the overall robustness of the catalytic system. Meanwhile, PPh₃ can easily dissociate to form vacant coordination sites, thereby enhancing catalytic activity. As a result, the Ru(Ⅱ)-NNN complex [Ru(L-NNN)Cl(PPh₃)₂]Cl (1, L-NNN=2,6-bis(5-methyl-1H-pyrazol-3-yl)pyridine) was not only quite stable, but also showed high activity for CO₂ hydrogenation to formate, achieving a TON of up to 150 000. In the mechanism study, based on the results of in-situ NMR, in-situ HPLC-HRMS spectra, and density functional theory calculations, it is speculated that the active intermediates with empty coordination sites are highly active species in CO₂ hydrogenation.
- CO₂ hydrogenation,
- Ru complex,
- NNN ligands,
- homogeneous catalysis
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沈阳化工大学材料科学与工程学院沈阳 110142

Efficient hydrogenation of CO2 realized by Ru-NNN complex

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通讯作者: 陈斌, bchen63@163.com

Efficient hydrogenation of CO₂ realized by Ru-NNN complex