Facile synthesis of polyoxometalate-thionine composite via direct precipitation method and its photocatalytic activity for degradation of rhodamine B under visible light

摘要

(TH)_3PW_(12) (TH=thionine, PW12=PW12O403-) composite was prepared by direct precipitation of TH and PW_(12). The (TH)_3PW_(12) was characterized via UV-vis spectrum, FT-IR, SEM, and BET surface area. PW_(12) was intact during the precipitation process. The composite has a bar-like shape and relatively large surface area (Langmuir surface of (TH)_3PW_(12) was 31.59m~2g~(-1), BET surface was 20.26m~2g~(-1)). Using the material as the photocatalyst, rhodamine B (RhB) was efficiently bleached and mineralized under visible light irradiation (λ>420nm). The kinetics of the photodecomposition follow the first-order reaction. The (TH)_3PW_(12) catalyst can be easily separated from the reaction system and has good stability for reuse.