Fabrication of binary g-C3N4/UU-200 composites with enhanced visible-light-driven photocatalytic performance toward organic pollutant eliminations

Abstract

In this study, g-C₃N₄/UU-200 heterojunction photocatalysts displaying superior photocatalytic activity for organic pollutant elimination under white LED light irradiation were fabricated via an in situ solvothermal method. The successful construction of a heterojunction between g-C₃N₄ and UU-200 was evidenced by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The improved photocatalytic degradation of rhodamine B (RhB) and tetracycline hydrochloride (TCH) over g-C₃N₄/UU-200 compared with that over the individual components can be attributed to the anchoring of the g-C₃N₄ layered structure on the UU-200 surface promoting the decrease of the bandgap of UU-200, as confirmed by ultraviolet–visible diffuse reflectance spectroscopy, and to the light-induced charge separation efficiency stemming from a suitable heterojunction structure, which was revealed by photoluminescence spectroscopy and electrochemical analyses. Specifically, the 40% g-C₃N₄/UU-200 composite showed the highest photocatalytic activity toward the degradation of RhB (97.5%) within 90 min and TCH (72.6%) within 180 min. Furthermore, this catalyst can be recycled four runs, which demonstrates the potential of the g-C₃N₄/UU-200 composite as an alternative visible-light-sensitive catalyst for organic pollutant elimination.