Cu掺杂BiVO_4微米片的水热合成和光催化性能

Hydrothermal Synthesis and Photocatalytic Properties of Cu-doped BiVO_4 Microsheets

以Bi(NO3)3.5H2O、NaVO3和Cu(NO3)2.3H2O为原料并以十六烷基三甲基溴化铵(CTAB)为结构导向剂通过水热法制备了Cu/BiVO4微米片晶体。采用XRD、XPS、SEM、HRTEM、UV-Vis、比表面积测试等对产品进行了表征。结果表明,2.0 g CTAB辅助水热法能够合成结晶度高且形貌规整的单斜白钨矿Cu/BiVO4微米片晶体,其长度为1.0～2.0μm,宽度为0.5～2.0μm,厚度在200～300 nm内。相比BiVO4颗粒,片状Cu/BiVO4样品的紫外–可见光吸收边发生了稍许红移,具有较小的能带隙。光催化结果说明,5.0wt%Cu/BiVO4微米片表现出最好的光催化活性,其速度常数k为5.89×10–2/min,可见光照射10 mg/L亚甲基蓝溶液60 min的光解率达100%。

Using Bi（NO3）35H20, NaVO3 and Cu（NO3）23H20 as raw materials, Cu-doped BiVO4 microsheets were synthesized by ultrasonic-hydrothermal process with cetyltrimethyl ammonium bromide （CTAB） as template. The as-prepared samples were investigated by XRD, XPS, SEM, HRTEM, UV-Vis and BET tests. The results reveal that uniform and well crystallized Cu/BiVO4 microsheets in monoclinic crystal structure, with length of 1.0-2.0 μm, width of 0.5-2.0 μm and thickness of 200-300 nm, could be obtained via an ultrasonic-hydrothermal route assisted by 2.0 g CTAB. Compared with BiVO4 particles, Cu/BiVO4 nanosheets show a little red shift in the absorption band, resulting in a narrowed band gap （〈2.4 eV）. For 5.0wt% Cu/ BiVO4 microsheet, its photodegradation rate constant K is 5.89 x10^-2/min and the best photocatalytic activity is found with a 100% degradation of methylene blue （MB） with 10 mg/L concentration under visible-light irradiation for 60 min.