Non-metal group doped g-C3N4 combining with BiF3:Yb3+, Er3+ upconversion nanoparticles for photocatalysis in UV–Vis–NIR region

Abstract

Broad spectrum response photocatalyst is crucial for making full use of sunlight and widely used in efficient photocatalytic degradation of organic dyes. In this work, upconversion luminescence boosted broadband photocatalysts based on BiF3:Yb3+, Er3+ nanoparticles (BFY) and the carbon nitride doped with various masses of barbituric acid (CNBx) semiconductor materials (BFY/CNBx) were successfully designed and produced for photocatalysis in UV–Vis–NIR region. Compared with pure g-C3N4, BFY/CNB0.5 composites have better photocatalytic performance attributed to the utilization of broadband spectrum energy and effective charge separation. After 30 min illumination by visible light, photodegradation efficiency of RhB reaches about 99.4% by using BFY-2/CNB0.5. A plot of C/C0 versus time indicates that the BFY-2/CNB0.5 can degrade about 64.7% of RhB in 80 min by NIR irradiation. Under simulated solar light, the sample of BFY-2/CNB0.5 reaches a maximum degradation efficiency of 98.0% within 15 min. The strengthened photocatalytic activity is due to the synergistic effect of CNB0.5 and upconversion materials. The active species utilized in the degradation process were examined using capture experiments. After four continuous photocatalytic cycles, about 94.0% of RhB solution is degraded. The photocatalytic mechanism of the composite photocatalysts is also analyzed in detail. The results indicate that the prepared BFY/CNB0.5 photocatalysts have good prospects in the field of environmental remediation.