Bi2MoS2O4 modified g-C3N4 photocatalytic degradation of Rhodamine B
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摘要: 为了降低石墨相氮化碳(g-C3N4)电子空穴的复合率,采用浸渍法成功制备了Bi2MoS2O4/g-C3N4异质结,并对其光催化性能进行了研究。紫外-可见漫反射光谱测得改性后的催化剂的吸收边由原来的470 nm红移至490 nm。探讨了负载比、催化剂投加量和pH对罗丹明B可见光降解率的影响。当Bi2MoS2O4占g-C3N4质量分数为18wt%、催化剂投加量为0.36 g/L时,该催化剂可在15 min内完全降解罗丹明B。自由基捕获实验和能带分析结果表明,该体系形成了一种II型电子转移机制,其主要活性物种为•O2−。Abstract: In order to reduce the recombination rate of graphite phase carbon nitride (g-C3N4) photocatalyst′s electron and holes, the Bi2MoS2O4/g-C3N4 heterojunction was successfully prepared by the impregnation method. The absorption edge of the modified catalyst is red-shifted from 470 nm to 490 nm as measured by ultraviolet-visible diffuse reflectance spectroscopy. The effects of loading ratio, catalyst dosage and pH on the visible light degradation rate of Rhodamine B were discussed. When the mass ratio of Bi2MoS2O4 to g-C3N4 is 18wt% and the catalyst dosage is 0.36 g/L, the catalyst can completely degrade Rhodamine B within 15 min. Free radical capture experiments and energy band analysis results show that the system has formed a type II electron transfer mechanism, the main active species is •O2−.
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Key words:
- heterojunction /
- bismuth thiomolybdate /
- impregnation /
- photocatalysis /
- degradation /
- g-C3N4 /
- Rhodamine B
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表 1 不同Bi2MoS2O4/g-C3N4异质结的命名
Table 1. Name of different Bi2MoS2O4/g-C3N4 heterojunctions
Sample code Details Bi2MoS2O4/g-C3N4 Composite material formed by loading Bi2MoS2O4 on g-C3N4 3wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 3wt% 8wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 8wt% 10wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 10wt% 15wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 15wt% 18wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 18wt% 20wt%Bi2MoS2O4/g-C3N4 Mass fraction of Bi2MoS2O4 in g-C3N4 is 20wt% -
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