摘要
采用溶胶-凝胶法制备了掺杂与负载相结合的光催化剂Fe/TiO2/MCM-41,通过考察掺杂金属种类和掺杂量,探讨了制备条件对复合材料性能的影响,并用XRD、BET、TEM和XPS对其进行表征。结果表明,Fe3+掺杂量为0.05%时,光降解初始浓度为25 mg/L的甲基橙溶液30 min后脱色率达到95%以上。Fe/TiO2/MCM-41是一种比表面积达349.77 m2/g的介孔材料,具有锐钛矿和金红石相的混晶结构;光催化剂中铁以+3价形式存在,表面羟基氧所占比例为37%,掺杂铁抑制了TiO2粒子的生长。将Fe/TiO2/MCM-41用于光催化氧化水中的对硝基苯甲酸,当催化剂投加量为0.5 g/L、对硝基苯甲酸初始pH为5、浓度为2×10-4mol/L时,紫外光照30 min后,对硝基苯甲酸降解率达到58%以上。
A supported and doped photocatalyst, Fe/TiO2/MCM-41, was prepared by sol-gel method. The preparation conditions of the composite such as metal type and doping quantity were be discussed. Tile Fe/TiO2/MCM-41 was characterized by XRD, BET, TEM and XPS. The results showed that Fe/TiO2/MCM-41 of the Fe doping content of 0.05 %, the decoloring rate of methyl orange （25 rag/L） reached 95 % under 30 rain UV-irradiation. Fe/TiO2/MCM-41 was a mesoporous material with the surface area of 349.77 m2/g and its crystalline phase was anatase and rutile phase. The analysis of XPS indicated that Fe exhibited ＋4 valence, and the percentage of hydroxyl oxygen at TiO2 surface was 37 %, and Fe doping control the growth of TiO2 particles. The photodegradation rate reached 58 % under 30 rain uv-irradiation with the dosage of 0.5 g/L of Fe/TiO2/MCM-41, the initial concentration of 2×10^-4 mol/L and the pH value of 5 of p-nitrobenzoic acid.
出处
《广东化工》
CAS
2013年第5期23-26,共4页
Guangdong Chemical Industry
