N-doped Ti3C2-reinforced porous g-C3N4 for photocatalytic contaminants degradation and nitrogen reduction.

Abstract

Herein, a series of N-doped Ti3C2/porous g-C3N4 composites are ultrasonically prepared from N-doped Ti3C2 and porous g-C3N4 under N2 atmosphere. The structure, morphology, and optical characteristics of the as-prepared composites are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, etc. Moreover, photocatalytic measurements show that N-doped Ti3C2 is an excellent modifier for porous g-C3N4 to heighten its photocatalytic activity. Only 44.1% of rhodamine B can be degraded by the photocatalysis of pristine porous g-C3N4, while the photocatalytic degradation ratio of rhodamine B can reach up to 97.5% for the optimal N-doped Ti3C2 loading composites under visible light for 15 min. Moreover, the photocatalytic tests of N2 fixation confirm that the optimal composites show the highest production yield of NH4+ (11.8 μmol gcat-1 h-1), which is 2.11-folds more than that of porous g-C3N4 (5.6 μmol gcat-1 h-1). The reinforced photocatalytic properties are revealed to profit from the more photogenerated electrons and holes' separation, higher ability for light response, and more abundant active sites. This work develops the route for boosting the photocatalytic properties of porous g-C3N4 with N-doped Ti3C2.