Asymmetric gradient orbital interaction of hetero-diatomic active sites for promoting C − C coupling

• Published in: Nature communications Vol. 14; no. 1; p. 3808
• Main Authors: Wang, Jin Ming, Zhu, Qin Yao, Lee, Jeong Heon, Woo, Tae Gyun, Zhang, Yue Xing, Jang, Woo-Dong, Kim, Tae Kyu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 27.06.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 140/146; 639/301/299/890; 639/638/675; 639/638/77/890; Acetic acid; Bonding strength; Carbon dioxide; Catalysts; Charge distribution; Collision dynamics; Copper; Coupling (molecular); Dihedral angle; Electrons; Energy; Engineers; Humanities and Social Sciences; Intermediates; Molecular orbitals; multidisciplinary; Photocatalysis; Photoreduction; Porphyrins; Science; Science (multidisciplinary); Selectivity; Skewed distributions; Symmetry; Transmission electron microscopy; Vibration
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-39580-5

Diatomic-site catalysts (DACs) garner tremendous attention for selective CO 2 photoreduction, especially in the thermodynamical and kinetical mechanism of CO 2 to C 2+ products. Herein, we first engineer a novel Zn-porphyrin/RuCu-pincer complex DAC (ZnPor-RuCuDAC). The heteronuclear ZnPor-RuCuDAC exhibits the best acetate selectivity (95.1%), while the homoatomic counterparts (ZnPor-Ru 2 DAC and ZnPor-Cu 2 DAC) present the best CO selectivity. In-situ spectroscopic measurements reveal that the heteronuclear Ru–Cu sites easily appear C 1 intermediate coupling. The in-depth analyses confirm that due to the strong gradient orbital coupling of Ru4 d –Cu3 d resonance, two formed * CO intermediates of Ru–Cu heteroatom show a significantly weaker electrostatic repulsion for an asymmetric charge distribution, which result from a side-to-side absorption and narrow dihedral angle distortion. Moreover, the strongly overlapped Ru/Cu- d and CO molecular orbitals split into bonding and antibonding orbitals easily, resulting in decreasing energy splitting levels of C 1 intermediates. These results collectively augment the collision probability of the two * CO intermediates on heteronuclear DACs. This work first provides a crucial perspective on the symmetry-forbidden coupling mechanism of C 1 intermediates on diatomic sites. Molecular insights into the selectivity mechanism of dual-atom sites are required to engineer efficient solar-fuel catalysts. Here, the authors reveal symmetry-forbidden coupling mechanism of C1 intermediates on diatomic sites by manipulating metal gradient orbital interaction over diatomic COFs.