摘要
单斜相BiVO4晶体的禁带宽度为2.4eV,可以响应可见光,是新型高效的催化材料。本研究以Bi(NO_3)_3·5H_2O和NaVO_3为原料,三正辛胺和正辛酸为相转移催化剂,选取不同表面活性剂,采用溶剂热法制备得到纳米级单斜相BiVO_4晶体。通过XRD,SEM,TEM和UV-vis光谱对样品的物相、形貌及吸光度进行表征,并通过可见光下降解亚甲基蓝实验测试样品的光催化性能。结果表明:合成材料为单斜白钨矿结构,晶粒均匀;不同的合成温度及前驱体pH对晶体的尺寸及形貌影响显著,进而影响光催化效率;在合成温度为160℃,pH为7,油胺作为表面活性剂时,样品为单分散球状晶体,亚甲基蓝降解效率最高。
Monoclinic BiVO_4 can respond to visible light and is regarded as a new efficient catalytic material. A controllable solvothermal method has been developed to synthesize monoclinic BiVO_4 in this research,using Bi(NO_3)_3·5H_2O and NaVO_3 as raw materials, trioctylamine and n-caprylic acid as phase transfer catalysts, and different types of surfactants.The phase structure,morphology and light absorbance of the obtained samples were characterized by XRD,SEM,TEM and UV-vis spectrum,respectively.The photocatalytic efficiencies were evaluated by the degradation of methylene blue under visible-light irradiation.Results showed that the particles are monoclinic phase with uniform size.By simply tuning the experimental parameters,such as reaction temperature and precursor pH,samples with a variety of sizes and shapes can be achieved,with different photocatalytic properties.The as-prepared BiVO_4 particles show excellent performance in dye degradation when synthesized temperature is 160℃,pH reaches 7 and oleylamine is used.
引文
[1]A.Walsh,Y.F.Yan,M.N.Huda,M.M.Al-Jassim,S.H.Wei.Chem.Mater.2009,21:547.
[2]X.Zhang,Z.H.Ai,F.L.Jia,L.Z.Zhang,X.X.Fan,Z.G.Zou.Mater.Chem.Phys.2007,103:162.
