纳米TiO2-Cu2O可见光下光催化降解活性艳红及其机理研究

Photocatalytic Degradation of the Reactive Brilliant Red and Its Mechanism over Nano-sized TiO2-Cu2O Under Visible Irradiation

中文关键词: 纳米Cu2O TiO2-Cu2O复合氧化物 活性艳红X-3B 光催化

英文关键词: nano-sized Cu2O, TiO2-Cu2O complex oxides, reactive brilliant red X-3B, photocatalysis

中文摘要:

      采用钛酸丁酯水解和肼还原醋酸铜的方法制备出TiO2-Cu2O复合氧化物，研究了TiO2-Cu2O复合光催化剂在可见光照射下光催化降解活性艳红X-3B的性能，考察了催化剂组成、催化剂投加量、溶解氧、H2O2等对光催化反应的影响，探讨了Cu2O及TiO2-Cu2O光催化降解有机污染物的机理。结果表明，由于TiO2和Cu2O之间存在协同作用，使得复合氧化物的活性比单一的Cu2O高。Cu2O光催化的氧化物种为·OH和光生空穴。光生电子(e-)还原吸附在Cu2O表面上的氧，产生超氧阴离子，然后再进一步生成·OH，光生空穴(h+)无法直接将吸附在Cu2O表面的OH-氧化成·OH。

英文摘要:

      A series of TiO2-Cu2O mixed oxides were prepared by the hydrolysis of titanium butoxide and reduction of copper acetate with hydrazine. The photocatalytic degradations of the reactive brilliant red X-3B over the TiO2-Cu2O were investigated under the irradiation with visible light. The effects of composition, amount of catalyst and the diluted oxygen as well as H2O2 were studied. In addition, the photocatalytic degradation mechanism of organic compounds over the Cu2O and TiO2-Cu2O was discussed. The results showed that the complex oxides exhibited higher activity than single Cu2O due to the synergetic effect between TiO2 and Cu2O. The oxidative species in Cu2O were believed to be free radical ·OH and electric holes. ·OH free radicals were originated from the super oxygen anions，which were produced from the reduction of oxygen absorbed on the surface of Cu2O by photoelectrons. The holes produced through light excitation could not oxidize OH- to ·OH directly.