尖晶石型Cu_(0.6)Ni_(0.4)Al_2O_4粉体的制备及其可见光性能

Preparation and visible light photocatalytic property of spinel Cu_(0.6)Ni_(0.4)Al_2O_4 particles

采用溶胶-凝胶法,800℃热处理制备了纳米Cu0.6Ni0.4Al2O4粉体,利用XRD和TEM对材料的结构和形貌进行了分析和表征。结果表明,所制Cu0.6Ni0.4Al2O4粉体的晶型为尖晶石晶体结构,粉体呈球状,粒径约为5～40nm。利用紫外-可见漫反射吸收光谱测得样品的极限吸收波长延伸至782nm,计算得到粉体的禁带宽度为1.59eV。在125W自镇流荧光高压汞灯(λ>400nm)的照射下,纳米尖晶石型Cu0.6Ni0.4Al2O4对偶氮染料活性艳红K-2G的2h降解率高达99%,而P-25(TiO2)纳米粉体在相同的降解实验条件下对染液的降解率不到10%。通过研究不同催化剂用量和染液降解率的关系,确定催化剂最佳用量为2g/L。

Spinel Cu0.6Ni0.4Al2O4 nanoparticles were synthesized at 800 ℃ for 3 h via the inorganic salt sol-gel approach.The powder were characterized by powder X ray diffraction(XRD) and transmission electron microscopy(TEM).The results reveal that the Cu0.6Ni0.4Al2O4 powders possess a spinel-type structure and particle sizes is 5-40 nm.The edge wavelength of absorption is located at 782 nm in the ultraviolet-visible diffuse reflectance spectrum,the band gap was calculated as about 1.59 eV.The photocatalytic activity was investigated by using reactive red K-2G under the irradiation of mercury-vapor lamp(λ>400).The resulting degradation rate of reactive red K-2G was measured to be as high as 99% in 2 h.However,the degradation rate of dye photocatalyzed in P-25(TiO2) nanopowder less than 10% in 2 h under the same experiment conditions.The connection between the degrading rate of reactive red K-2G and the dosage of catalyst was studied,the results indicate that the optimal dosage of Cu0.6Ni0.4Al2O4 is 2 g/L.