Influences of Gd Substitution on the Crystal Structure and Visible-Light-Driven Photocatalytic Performance of Bi2WO6

Different samples of gadolinium (Gd)-doped Bi2WO6 were obtained by hydrothermal means, and their photocatalytic activities for degradation of rhodamine B (RhB) under visible-light irradiation were researched. The successful incorporation of Gd3+ ions into Bi2WO6 was detected by XRD and XPS, and the prepared samples have also been characteriazed by SEM, TEM, HRTEM, DRS, and PL. The results suggested that Gd doping has great influences on the visible-light photocatalytic activity as well as the microstructure. Appropriate doping content greatly improve photocatalytic activity due to the electron shallow-trapping mechanism for the efficient separation of electron and hole pairs, and the 1% Gd–Bi2WO6 sample with flower-like structure exhibited the highest photocatalytic activity. It has already been confirmed by photocurrent generation and electrochemical impedance spectra. The present research provides a simple and valid method for improving the visible-light-responding photocatalytic activity and fabricating hierarchical architectures of Bi2WO6.