Novel Tm3+/Yb3+–co-doped Bi2MoO6: Synthesis, characterization, and enhanced photocatalytic activity under visible-light irradiation

A novel photocatalyst Tm 3+ /Yb 3+ –co-doped bismuth molybdate (Bi 2 MoO 6 ) were synthesized via the hydrothermal method. The samples were characterized through X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra, and photoluminescence. XPS characterization confirmed the doped rare earth elements. Analysis of the optical properties explained the up-conversion process and its effect on the photocatalytic performance. The as-synthesized samples were employed to decompose Rhodamine B to value its photocatalytic activities under visible light irradiation. The doped samples showed an enhanced photocatalytic activity compared with the bare Bi 2 MoO 6 . When the ratio of Tm 3+ and Yb 3+ was 0.5:5, the degradation efficiency was the highest of 96.1% within 25 min, which was higher than that (74.9%) of pure Bi 2 MoO 6 . Moreover, the photocatalytic mechanism of improving the photocatalytic properties was discussed. Besides, the sample showed a super stability in photocatalytic activity. A novel catalyst for industrial pollutant degradation was proposed.