BiVO4/MIL-100(Fe)复合材料光催化降解结晶紫

Photocatalytic Degradation of Crystal Violet with BiVO4/MIL-100(Fe) Composites

摘要:

以NH4VO3、Bi(NO3)3•5H2O、均苯三酸、 Fe(NO3)3•9H2O为主要原料，采用一锅水热法制备了BiVO4/MIL-100(Fe)复合材料，利用XRD、SEM、N2吸附-脱附、UV-Vis DRS及PL对复合材料的结构、形貌、比表面积以及光学性能进行了表征。XRD显示具有较大比表面积的复合材料中BiVO4为单斜相、四方相的混晶结构，其对可见光的吸收强度高于MIL-100(Fe)，吸收光后产生的光生电子、空穴的复合率较低。可见光条件下，不同材料对结晶紫的光催化降解实验中，BiVO4/3MIL-100(Fe)的光催化活性最佳。实验结果表明：光照射50 min，30 mg BiVO4/3MIL-100(Fe)对30 mL质量浓度30 mg/L结晶紫的降解率为98.7%，主要光催化活性基团是h+。此外，日光下该材料对结晶紫、罗丹明B、亚甲基蓝也有较强的光降解能力。

Abstract:

BiVO4/MIL-100(Fe) composites were prepared by one-pot hydrothermal method using NH4VO3, Bi(NO3)3•5H2O, 1,3,5-benzenetricarboxylic acid and Fe(NO3)3•9H2O as raw materials. The structure, morphology, specific area and optical property of BiVO4/MIL-100(Fe) composites were characterized by XRD, SEM, N2 adsorption-desorption, UV-Vis DRS and PL. The composites had larger specific surface area. XRD results showed that BiVO4 had mixed crystal structure of monoclinic phase and tetragonal phase. The absorption intensity of BiVO4/MIL-100(Fe) composites for visible light was higher than that of MIL-100(Fe). The recombination rate between photogenerated electrons and holes decreased after the composites absorbed visible light. Different materials were used as catalysts for the photodegradation of crystal violet under visible light. Among them, BiVO4/3MIL-100(Fe) composites displayed the highest photocatalytic activity. The results revealed that the degradation rate of 30 mg BiVO4/3MIL-100(Fe) composites for 30 mL crystal violet solution with an initial concentration of 30 mg/L was 98.7% under visible light irradiation for 80 min. The holes were main active catalytic species. Besides, BiVO4/3MIL-100(Fe) composites exhibited stronger photocatalytic degradation ability for crystal violet, rhodamine B and methylene blue under sunlight irradiation.