Cu-phen Coordination Enabled Selective Electrocatalytic Reduction of CO2 to Methane

Haiyan Hu; Shiting Qian; Qin Shi; Minxing Du; Ning Sun; Yong Ding; Jun Li; Qiquan Luo; Zhen Li; Lin He; Yuxia Sun; Yuehui Li

doi:10.1021/acsami.4c02810

Cu-phen Coordination Enabled Selective Electrocatalytic Reduction of CO₂ to Methane

ACS Appl Mater Interfaces. 2024 May 1;16(17):22025-22034. doi: 10.1021/acsami.4c02810. Epub 2024 Apr 18.

Authors

Haiyan Hu^{1

2

3}, Shiting Qian⁴, Qin Shi^{1

3}, Minxing Du¹, Ning Sun⁵, Yong Ding^{1

2}, Jun Li⁵, Qiquan Luo⁴, Zhen Li¹, Lin He¹, Yuxia Sun¹, Yuehui Li¹

Affiliations

¹ State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization; State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou 730000, P. R. China.
² State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Advanced Catalysis of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.
³ University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
⁴ School of Chemistry and Chemical Engineering, School of Materials Science and Engineering, Institute of Physical Science and Information Technology, Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, Anhui P. R. China.
⁵ Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.

PMID: 38634322
DOI: 10.1021/acsami.4c02810

Abstract

Manipulation of selectivity in the catalytic electrochemical carbon dioxide reduction reaction (eCO₂RR) poses significant challenges due to inevitable structure reconstruction. One approach is to develop effective strategies for controlling reaction pathways to gain a deeper understanding of mechanisms in robust CO₂RR systems. In this work, by precise introduction of 1,10-phenanthroline as a bidentate ligand modulator, the electronic property of the copper site was effectively regulated, thereby directing selectivity switch. By modification of [Cu₃(btec)(OH)₂]_n, the use of [Cu₂(btec)(phen)₂]_n·(H₂O)_n achieved the selectivity switch from ethylene (faradaic efficiency (FE) = 41%, FE_C2+ = 67%) to methane (FE_CH₄ = 69%). Various in situ spectroscopic characterizations revealed that [Cu₂(btec)(phen)₂]_n·(H₂O)_n promoted the hydrogenation of *CO intermediates, leading to methane generation instead of dimerization to form C₂₊ products. Acting as a delocalized π-conjugation scaffold, 1,10-phenanthroline in [Cu₂(btec)(phen)₂]_n·(H₂O)_n helps stabilize Cu^δ+. This work presents a novel approach to regulate the coordination environment of active sites with the aim of selectively modulating the CO₂RR.

Keywords: 1,10-phenanthroline; CO2 electroreduction; Cu−N coordination; metal coordination polymers; selectivity switch.