采用溶胶援胶法制备了稀土掺杂的系列光催化剂RE/TiO2(La/TiO2,Eu/TiO2,Y/TiO2,Pr/TiO2,Nd/TiO2,Sm/TiO2,Gd/TiO2),XRD晶相结构表征分析表明稀土离子的掺杂有效抑制了TiO2晶粒的增长。分别考察了不同酸、醇为牺牲剂时RE/TiO2对光催化产氢性能的影响。实验结果表明:以乙醇为牺牲剂时,稀土的掺杂均提高了光催化产氢性能;以乙酸为牺牲剂时,只有铕和镧的掺杂提高了光催化活性。以La/TiO2为光催化剂,甲醇、乙醇和正丙醇为牺牲剂,光催化产氢活性顺序为:乙醇〉甲醇〉正丙醇;以Eu/TiO2为光催化剂,以甲酸、乙酸和丙酸为牺牲剂,光催化产氢活性依次为:甲酸〉丙酸〉乙酸;因此,牺牲剂的选择对光催化产氢活性有重要的影响。
A series of RE/TiO2 ( La/TiO2, Eu/TiO2, Y/TiO2, Pr/TiO2, Nd/TiO2, Sm/TiO2, Gd/TiO2 ) photocatalyst powders were prepared by sol-gel method. The characterization by XRD showed that the TiO2 doped with small amount of rare earth ions could effectively restrain growth of TiO2 particle. The effects of various sacrificial reagents such as acids and alcohols, on photoeatalytic H2 activity were investigated. The experimental results showed that the photocatalytic H2 activity of RE/TiO2 was enhanced by doping with rare earth ions when ethanol was used as sacrificial rea gent. On the other hand, using acetic acid as sacrificial reagent, photocatalytic H2 activity of RE/TiO2 was enhanced only by doping with Eu and La ions. Using La/TiO2 as photocatalyst and alcohols as sacrificial reagent, the photocatalytic H2 activity changed in order of ethanol 〉 methanol 〉 propanol. However, when Eu/ TiO2 used as photocatalyst and acids as sacrificial reagent, the photocatalytic H2 activity changed in order of formic acid 〉 propionic acid 〉 acetic acid. Therefore,the choice of various sacrificial reagents had a great effect on photocatalytic HE production.