? ?光诱导 ? Pt/g-C₃N₄纳米 片甲酸氧化性能的研究

By using graphitic carbon nitride nanosheet (g-C₃N₄nanosheet) as a support，Pt/g-C₃N₄nanosheet catalyst was fabricated by microwave assisted polylol process. The nanoparticles size,composition，structure and optical properties of Pt/g-C₃N₄nanosheet were characterized by TEM，XRD，XPS and UV-Vis diffuse reflectance spectroscopy. Comparing with the catalytic activities toward formic acid electro-oxidation under dark and visible light illumination，the superior activity of Pt/g-C₃N₄nanosheet catalyst was achieved under visible light illumination. This visible light-driven enhancement in the formic acid performance could be attributed to the plasmon-induced electron-hole separation on g-C₃N₄with visible light illumination. The photo-generated hot electron promoted the oxidation of formic acid molecules. The current density of g-C₃N₄nanosheet was increased under visible light illumination in the presence of formic acid. More importantly，the fast electron transfer from Pt to g-C₃N₄nanosheet under visible light illumination adjusted the electronic structure of Pt. The "electron deficient" state of Pt could weaken the adsorption energy of CO (as a poisoning species)，facilitating CO oxidation. The rapid removal of poisoning species on Pt would provide more catalytic activity sites for the oxidation of formic acid，enhancing formic acid catalytic activity. The visible light-assisted enhancement in the electrochemical formic acid activity provides a development strategy for direct formic acid fuel cells.