优化了La掺杂Bi
2WO
6光催化剂的水热制备工艺。考察了掺杂量、反应液初始pH值、水热时间、焙烧温度及焙烧时间等条件因素对La掺杂
Bi
2
WO
6在模拟太阳光下光催化降解4-氯酚(4-CP)性能的影响。结果表明:La掺杂量为1.5 wt%,反应液初始pH值为7,160℃水热12 h,经500℃焙烧2 h,制备的La掺杂
Bi
2
WO
6的光催化性能最佳,在模拟太阳光照射下对4-CP光催化去除率达51%,明显高于
Bi
2
WO
6的光催化活性(38.4%)。
The hydrothermal synthesis process of La-doped
Bi
2
WO
6 photocatalyst was optimized. The effects of various factors including La-doping amount, initial pH of reactant solution, hydrothermal time, calcination temperature, and calcination time on the photocatalytic activity of La-doped
Bi
2
WO
6 were investigated through the photocatalytic degradation of 4-chlorophenol (4-CP) under simulated sunlight irradiation. The results show optimal preparation conditions as follows: La-doping amount is 1.5 wt%, and the initial pH value of reactant solution is 7, and hydrothermal time at 160˚C is 12 h, and calcination temperature is 500˚C, and calcination time is 2 h. The photoactivity of as-prepared La-doped
Bi
2
WO
6 was 51%, which is much higher than that of undoped
Bi
2
WO
6 prepared under the same conditions (38.4%).
将Bi(NO3)3·5H2O和Na2WO4·2H2O分别按摩尔比2:1的比例称取,再称取一定量的La2O3,将4.85 g Bi(NO3)3·5H2O和La2O3溶于3.5 mL 4 M稀硝酸,1.65 g Na2WO4·2H2O溶解在5 mL 2M NaOH溶液中,将Na2WO4溶液逐滴加入Bi(NO3)3和La2O3的混合溶液中,用2 M NaOH溶液调节混合物的pH值,持续搅拌1 h后将混合物移入50 mL水热反应釜中,在160℃水热一定时间,常温下冷却。然后,将制得的淡黄色沉淀用蒸馏水洗涤3次,于110℃下在真空干燥24 h,在一定温度下焙烧得到La掺杂Bi2WO6样品。
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