《Angew. Chem. Int. Ed.》: Highly Active Photoreduction of Atmospheric-Concentration CO₂ into CH₃COOH over Palladium Particles on Nb₂O₅ Nanosheets

Jinyu Ding,⁺ Peijin Du,⁺ Peipei Li,⁺ Wenxiu Liu, Jiaqi Xu,* Wensheng Yan, Yang Pan, Jun Hu, Junfa Zhu, Qingxia Chen,^* Xingchen Jiao,^* and Yi Xie^*

The endeavor to drive CO₂ photoreduction towards the synthesis of C₂ products is largely thwarted by the colossal energy hurdle inherent in C−C coupling. Herein, we load active metal particles on metal oxide nanosheets to build the dual metal pair sites for steering C−C coupling to form C₂ products. Taking Pd particles anchored on the Nb₂O₅ nanosheets as an example, the high-angle annular dark-field image and X-ray photoelectron spectroscopy demonstrate the presence of Pd−Nb metal pair sites on the Pd-Nb₂O₅ nanosheets. Density functional theory calculations reveal these sites exhibit a low reaction energy barrier of only 1.02 eV for C−C coupling, implying that the introduction of Pd particles effectively tailors the reaction step to form C2 products. Therefore, the Pd-Nb₂O₅ nanosheets achieve a CH₃COOH evolution rate of 13.5 μmol g⁻¹ h⁻¹ in photoreduction of atmospheric-concentration CO₂, outshining all other single photocatalysts reported to date under analogous conditions.

Figure 1. Schematic illustration for photoreduction of atmospheric-concentration CO₂ on the active metal particles anchored on metal oxide semiconductor nanosheets. The metal pair sites promote the C–C coupling step.