AgBr/Ag_(2)CrO_(4)复合光催化剂的制备及其光催化性能

Synthesis and photocatalytic activity of AgBr/Ag_(2)CrO_(4)composite photocatalyst

以硝酸银和铬酸钾为原料,采用简单的水热法制备Ag_(2)CrO_(4),再通过沉淀法合成复合不同质量分数AgBr的AgBr/Ag_(2)CrO_(4)复合光催化剂,并对产物进行通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外漫反射仪(DRS)和荧光光谱分析仪(PL)等表征。结果表明:水热法所得Ag_(2)CrO_(4)为块状微米结构,粒径约为20μm;不同质量分数的AgBr复合Ag_(2)CrO_(4)后,粒径明显变小,约为1μm。以亚甲基蓝为目标分解物,考察了复合不同质量分数AgBr的AgBr/Ag_(2)CrO_(4)复合催化剂光催化性能,结果表明,复合光催化剂的催化性能更佳;在模拟自然光照下,0.10g复合质量分数为90%AgBr的AgBr/Ag_(2)CrO_(4),降解亚甲基蓝溶液(100mL,10mg/L)10min后,降解率高达97.7%,是相同条件下商用TiO2对亚甲基蓝降解率的5倍。

Ag_(2)CrO_(4)was prepared by simple hydrothermal process using silver nitrate and potassium chromate as raw materials,and then AgBr/Ag_(2)CrO_(4)composite photocatalysts with different mass fractions of AgBr were synthesized by precipitation method.The samples were characterized by XRD,SEM,DRS and PL.The results revealed that the Ag_(2)CrO_(4)obtained by hydrothermal method was bulk micron structure with a particle size of about 20μm.After compounding Ag_(2)CrO_(4)with different mass fractions of AgBr,the particle size of AgBr/Ag_(2)CrO_(4)obviously decreased to about 1μm.The photocatalytic properties of AgBr/Ag_(2)CrO_(4)composite catalyst with different mass fractions of AgBr were explored with methylene blue(MB)as the target decomposer.The results showed that the photocatalytic property of the composite photocatalyst was better than those of the single-phase AgBr or Ag_(2)CrO_(4).0.1g AgBr/Ag_(2)CrO_(4)composite catalyst,compounded with 90%mass fractions AgBr,exhibited the highest degradation rate of 97.7%after degrading MB solution(100mL,10mg/L)for 10 min under simulated natural light,which was 5 times that of commercial TiO_2 under the same conditions.