Enhanced Visible-Light-Driven H-2 Evolution Activity of g-C3N4 Photocatalysts via Calix[4]arene Dye Hybridization

Hybrid photocatalysts composed of a calixarene dye, C4BTP, with pyridine anchors and graphite-phase carbon nitrite (g-C3N4) are prepared by a facile solution impregnation method, and their photocatalytic performances are evaluated in visible-light-driven H-2 evolution after loading Pt nanoparticles. The optimal Pt/C4BTP-C3N4 (0.25 wt %) photocatalyst exhibits remarkable H-2 generation activity (40.57 mmol g(-1) h(-1) based on the mass of the catalyst and a corresponding turnover frequency of 26,157 h(-1) based on the amount of C4BTP in 5 h) and performs with good stability for 66 h (a turnover number of 577,950), which is the highest among all the reported dye-sensitized g-C3N4 visible light catalytic systems, significantly outperforming Pt/g-C3N4. This enhancement can be explained by the increased light collecting efficiency and improved charge separation and transfer for C4BTP-C3N4. This study provides an interesting example for the development of a highly efficient photocatalytic system based on dye-sensitized g-C3N4 catalysts for the chemical utilization of solar energy.