Optimizing reaction paths for methanol synthesis from CO₂ hydrogenation via metal-ligand cooperativity

As diversified reaction paths exist over practical catalysts towards CO₂ hydrogenation, it is highly desiderated to precisely control the reaction path for developing efficient catalysts. Herein, we report that the ensemble of Pt single atoms coordinated with oxygen atoms in MIL-101 (Pt₁@MIL) induces distinct reaction path to improve selective hydrogenation of CO₂ into methanol. Pt₁@MIL achieves the turnover frequency number of 117 h^-1 in DMF under 32 bar at 150 °C, which is 5.6 times that of Pt_n@MIL. Moreover, the selectivity for methanol is 90.3% over Pt₁@MIL, much higher than that (13.3%) over Pt_n@MIL with CO as the major product. According to mechanistic studies, CO₂ is hydrogenated into HCOO* as the intermediate for Pt₁@MIL, whereas COOH* serves as the intermediate for Pt_n@MIL. The unique reaction path over Pt₁@MIL not only lowers the activation energy for the enhanced catalytic activity, but also contributes to the high selectivity for methanol.