CO2 Reduction Catalyzed by Mercaptopteridine

摘要

The catalytic reduction of CO22 is of great interest since it plays a significant role in climate change and the global energy cycle. Inspired by the role of pterin in biological systems as a redox mediator and C1 carrier, we studied 6,7-dimethyl-4-hydroxy-2-mercaptopter 6,7-dimethyl-4-hydroxy-2-mercaptopteridine (PTE) to catalyze CO2 reduction on the glassy carbon electrode. In bulk electrolysis of a saturated CO2 solution in the presence of the PTE catalyst, Fourier transform infrared data show the progression of carbarmate intermediate and reduced products, including formate, formaldehyde and methanol. 13C NMR spectroscopy and gas chromatography data prove the production of methanol with a Faradaic efficiency of 10-23%. A multiple hydride transfer mechanism is proposed for the progressive multi-electron reduction of CO2 . PTE is proved to catalyze the reduction of CO 2 at low overpotential and without the involvement of any metal.;Photochemical CO2 reduction was studied by using CdSe quantum dots as a photosensitizer. Transient absorbance spectroscopy in the ultraviolet spectral region proves the electron transfer from quantum dots to PTE catalyst. The photo-generated 1 e reduced PTE is formed. However, the active form of catalysis should be the 2 e- reduced PTE, which calls for future work.