Modification Of Molybdenum(Vanadium) Bismuth Semiconductor And Study On Visible Light Catalytic Performance

In this paper,two photocatalytic materials（Ag₂WO₄/Bi₂MoO₆、Ag IO₃/BiVO₄-GO）were prepared by constructing heterojunction and adjusting morphology.A series of characterization of the prepared sample was carried out.The photocatalytic properties of the samples were evaluated by degrading methylene blue（MB）,rhodamine B（Rh B）and tetracycline hydrochloride（TC）under visible light irradiation.The degradation mechanism was further discussed by capture experiments.The specific contents are as follows:1.Bi₂MoO₆ was prepared by using Bi（NO₃）₃·5H₂O and Na₂MoO₄·2H₂O as raw materials and ethylene glycol and ethanol as solvent.Ag₂WO₆/Bi₂MoO₆ complexes with different mole percentages were prepared by precipitation method.The crystallization,optical properties and morphological properties of the prepared materials were studied by XRD,UV-Vis DRS,PL,PT,EIS,BET and SEM,respectively.The photocatalytic performance of Z-Ag₂WO₄/Bi₂MoO₆ photocatalyst was evaluated by degradation of methylene blue（MB）under visible light irradiation.The results showed that Ag₂WO₄ was evenly dispersed on Bi₂MoO₆ after the composite,which reduced the agglomeration of Ag₂WO₄.The absorption range of the composite in visible light was widened.The 30%Ag₂WO₄/Bi₂MoO₆ samples possess the best photocatalytic activity.Based on the characterization results,it can be inferred that the improvement of photocatalytic activity can be attributed to the synergistic effect of Ag₂WO₄/Bi₂MoO₆ composites,which lead the lower electron-hole composite rate and the higher electron-hole separation efficiency.Finally,we studied the active groups that play a major role in the reaction process through the capture experiment,and proposed the possible degradation mechanism.2.Spherical BiVO₄ was prepared under mild conditions by solvent heat method,which taking Bi（NO₃）₃·5H₂O and NH₄VO₃ as raw materials,using H₂O:CH₃COOH:C₂H₅OH=3:1:1（volume ratio）as solvent.The Ag IO₃/BiVO₄ complexes with different mass ratios were obtained by using the precipitation method.The final product Ag IO₃/BiVO₄-GO compounds was obtain combined 20%Ag IO₃/BiVO₄ with graphene by water bath.The composition,optical properties and morphological properties of the prepared materials were studied by XRD,XPS,uv-vis DRS,PL,PT,EIS,TEM and SEM,respectively.The photocatalytic properties of Ag IO₃/BiVO₄-GO composites were evaluated by degrading rhodamine B（Rh B）and tetracycline hydrochloride under visible light irradiation.The results showed that the photocatalytic activity of the composite material was significantly improved,and the recombination rate of electron and hole was obviously decreased.The Ag IO₃/BiVO₄-1%GO had the best degradation effect.In addition,the stability of the composite samples was studied.The catalytic activity of the Ag IO₃/BiVO₄-1%GO samples was still high after the four-wheel cycle experiment.At the same time,we conducted capture experiments to explore the active groups that play a major role in the reaction process and proposed possible degradation mechanisms.