Copper-based (Cu) materials are known for their ability to convert CO 2 into high-value hydrocarbons through the CO 2 RR. However, their stability, particularly in acidic media, requires enhancement. Metallic Pt exhibits excellent stability in both acidic and alkaline environments, yet its competitive activity in the hydrogen evolution reaction (HER) limits its application in CO 2 RR.
By constructing composite materials with metal-doped molecules, the modified molecules can be stably retained at the interface. This distinctive structure allows for the adjustment of the metal interface properties while increasing the contact between reactants and active sites. It effectively controls the adsorption intensity of key intermediates, thereby influencing catalytic performance.
Professor He’s team employed a molecular doping strategy to encapsulate a substantial number of thionine (Th) molecules within Pt nanocrystals, resulting in the formation of PtNPs@Th catalysts. These entrapped Th molecules are securely confined around the Pt surface, significantly altering the catalytic activity of metallic Pt. As a result, the conventional HER activity of Pt-based materials is largely suppressed, while the CO 2 RR performance is markedly improved in both strongly acidic (pH = 1) and weakly acidic (pH = 4.2) electrolytes. Importantly, due to the robust corrosion resistance of metallic Pt, the PtNPs@Th catalyst can maintain catalytic stability in acidic media for over 100 hours. The combination of theoretical calculations and in-situ characterization has confirmed that the synergistic effect of Th molecules and Pt facilitates the production of CH 4 from CO 2 RR. This research opens new avenues for the application of molecularly decorated reaction interfaces in diverse electrocatalysis.
National Science Review