BiVO_4催化剂的制备及其光催化还原CO_2的研究

Preparation of BiVO_4 catalyst and photocatalytic reduction of CO_2

采用化学沉淀法制备BiVO4光催化剂并应用于光催化还原CO2/H2O体系中。通过TG-DTA、FTIR、XRD对光催化剂进行表征,研究了pH和焙烧温度等对光催化性能的影响。结果表明,pH=7并于600℃煅烧制得的单斜相BiVO4活性最高。在催化剂用量为0.6 g/L,反应时间为7 h,CO2流量为200 mL/min,反应温度为80℃,反应液中NaOH和Na2SO3的浓度均为0.10 mol/L条件下,甲醇产率高达249.18μmol/g。并对BiVO4催化剂光催化还原CO2的机理进行了探究。

BiVO4 photocatalyst is prepared by chemical precipitation method.Its photocatalytic reduction of CO2 in water is examined.The catalyst is characterized by TG-DTA,FTIR and XRD.The effects of pH value,roasting temperature and other conditions on the activity of photocatalytic reduction of CO2 are studied.The results show that monoclinic phase BiVO4 prepared at pH 7 and calcined at 600℃ has the highest activity.The yield of methanol can reach 249.18 μmol/g under the following conditions： 0.6 g/L of the amount of catalyst,7 hours of the reaction time,200 mL/min of CO2,80℃ of the reaction temperature,0.10 mol/L of the concentration of NaOH and Na2SO3.The mechanism of photocatalytic reduction of CO2 by BiVO4 catalyst is studied.