Abstract:YVO₄ photocatalysts are prepared by hydrothermal reaction method and modified by C and Sm³⁺, and their morphological structures, compositions and properties are characterized by XRD(X-ray diffraction), SEM(scanning electronic microscopy), and BET(specfic surface area).YVO₄ photocatalysts and modification products of YVO₄ are used to remove gaseous elemental mercury under UV light.The mercury remove efficiency of YVO₄, YVO₄/C, YVO₄:Sm³⁺ and YVO₄/C:Sm³⁺ are 10.5%, 9.1%, 5.2% and 19.6% respectively.Although the sample YVO₄/C:Sm³⁺ has the highest efficiency, it is only 19.6%, which may be due to the UV light exciting the electron on the conduction band of YVO₄ and the successful transition of the electron to the valence electron.The reaction of photogenerated charge carriers energy is too weak to inspire freedom ·OH.Then only photo-generated carriers can oxidize mercury, which results in the fact that the samples do not possess the great mercury removal efficiency.