Hydrothermal preparation of flower-like Ni2+ doped Bi2WO6 for enhanced photocatalytic degradation

Abstract

Organic wastewater, especially dye wastewater, has become a severe pollutant threatening environmental health. Photocatalysis is considered a promising technology for wastewater treatment; therefore, Bismuth-based photocatalytic materials have been heavily investigated. In this paper, flower-like Ni2+ doped Bi2WO6 was successfully prepared by hydrothermal method. XRD, XPS, Raman, FT-IR, SEM, EDS, PL, EIS, UV–Vis DRS and transient photocurrent response were tested to analyze the structure, morphology, optical properties, and photocatalytic activity of the materials. The photocatalytic performance of Ni2+ doped Bi2WO6 was measured by degrading Rhodamine B (RhB). The results exhibit that the best photocatalytic degradation rate of RhB, reaching 93%, was achieved using 0.25% Ni2+ doped Bi2WO6. The characterization results demonstrated that Ni2+ successfully entered Bi2WO6 and supplanted Bi3+ in part. The enhanced photocatalytic performance is due to the generation of defects and the reduced band gap width in Ni2+ doped Bi2WO6. Furthermore, according to capture experiments, the effective reactive group is the superoxide radical. Therefore, Ni2+ doped Bi2WO6 catalyst holds some promise for application.