《Angew. Chem. Int. Ed.》: Light-Driven C-C Coupling for Targeted Synthesis of CH₃COOH with Nearly 100% Selectivity from CO₂

Jinyu Ding,⁺ Peijin Du,⁺ Juncheng Zhu,⁺ Qing Hu, Dongpo He, Yang Wu, Wenxiu Liu, Shan Zhu, Wensheng Yan, Jun Hu, Junfa Zhu, Qingxia Chen,^* Xingchen Jiao,^* and Yi Xie^*

Targeted synthesis of acetic acid (CH₃COOH) from CO₂ photoreduction under mild conditions mainly limits by the kinetic challenge of the C−C coupling. Herein, we utilized doping engineering to build charge-asymmetrical metal pair sites for boosted C−C coupling, enhancing the activity and selectivity of CO₂ photoreduction towards CH₃COOH. As a prototype, the Pd doped Co₃O₄ atomic layers are synthesized, where the established charge-asymmetrical cobalt pair sites are verified by X-ray photoelectron spectroscopy and X-ray absorption near edge spectroscopy spectra. Theoretical calculations not only reveal the charge-asymmetrical cobalt pair sites caused by Pd atom doping, but also manifest the promoted C−C coupling of double *COOH intermediates through shortening of the coupled C−C bond distance from 1.54 to 1.52 Å and lowering their formation energy barrier from 0.77 to 0.33 eV. Importantly, the decreased reaction energy barrier from the protonation of two*COOH into *CO intermediates for the Pd-Co₃O₄ atomic layer slab is 0.49 eV, higher than that of the Co₃O₄ atomic layer slab (0.41 eV). Therefore, the Pd-Co₃O₄ atomic layers exhibit the CH₃COOH evolution rate of ca. 13.8 μmol g⁻¹ h⁻¹ with near 100% selectivity, both of which outperform all previously reported single photocatalysts for CO₂ photoreduction towards CH₃COOH under similar conditions.

Link: https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202400828

Figure 1. Schematic illustration for (a) traditional CH₃COOH synthesis route at high temperature and pressure and (b) the designed environmentally friendly CH₃COOH synthesis route form CO₂ photoreduction under mild conditions.