采用低温水热法合成了一系列BiVO4样品,以XRD、SEM、UV-Vis DRS、BET等测试技术对样品的晶相结构、形貌、吸光性能以及比表面积等进行了表征,以MB染料分子模拟环境污染物,考察了样品的光催化性能.探讨了不同起始溶液浓度对样品的形貌及其光催化性能的影响.结果表明,水热反应中,起始溶液浓度对BiVO4样品的形貌和尺寸有很大影响,当起始溶液浓度为0.01mol/L时,所得样品呈“海藻头”形;浓度为0.05和0.1mol/L时,所得BiVO4均呈“鹅卵石”形;浓度为0.5mol/L时,所得BiVO4呈“土豆”形.光催化实验结果表明,“海藻头”和“鹅卵石”形BiVO4具有较高的光催化降解能力,光催化反应180min后,对MB溶液脱色率达到75％左右,而“土豆”形BiVO4仅达到45％.此外,对低温水热反应过程中BiVO4样品的形成机理进行了探讨.%A series of BiVO4 photocatalysts were synthesized via hydrothermal process.XRD,SEM,TGA,UV-Vis diffusion spectra were employed to characterize the phase structure,morphology and optical absorption properties of the samples.Using the degradation of MB as a model reaction,the photocatalytic property of the BiVO4 was detected.Results indicated that the concentration of starting solution had an important effect on the morphological evolution and photocatalytic property of BiVO4.When c (Bi3-) was 0.01,0.05 and 0.1,0.5 mol/L,the obtained BiVO4 samples possessed "seaweed-like","cobblestone-like" and "potato-like" morphology,respectively."seaweed-shaped" and "cobblestone-shaped" BiVO4 exhibited better photocatalytic property than "potato-shaped" BiVO4,and the decolorization efficiency of MB solution reached about 75％ at 180min.In addition,the formation mechanisms of BiVO4 with different morphology were discussed in detail.
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