氮元素掺杂CdS/TiO_2复合光催化剂的制备及表征

The Preparation and Characterization of N-Doped CdS/TiO_2 Composite Photocatalyst

以尿素(UA)和TiO_2-P_(25)为原料,经浸渍-焙烧制备出N-TiO_2,经水热法合成出CdS/N-TiO_2复合光催化剂。催化剂的分析表征结果表明,N进入TiO_2的晶格,占据了O的空位,由于N和O的电负性不同,使Ti周围的电子云密度变化;掺杂N后,TiO_2晶型未发生变化,电荷分离效率提高,吸收边发生红移;CdS/N-TiO_2复合光催化剂是CdS与N-TiO_2光学性质的综合表现,扩展了TiO_2的光响应范围,提高了电子-空穴的分离效率,颗粒分布均匀,有利于电荷传输,光催化活性提高,可见光催化分解硫化氢制氢速率可达10327.4μmol/(h·g),高于未掺杂改性的CdS/TiO_2。

The N-TiO2 was firstly prepared with UA and TiO2-P25 as raw materials,then the CdS/N-TiO2 composite photocatalysts had been prepared by hydrothermal method.The results of analysis and characterization showed that the N had incorporated into the lattice of TiO2 and occupied the O sites which altered the electron density around Ti.It was indicated from the photocatalytic decomposition of H2S to produce H2 over the above photocatalysts that the photocatalytic properties of CdS/N-TiO2 composite photocatalysts had been evidently improved as a result of a noticeable shift to visible region and the enhancement of the charge separation efficiency.The H2 evolution rates reached 10327.4μmol/(h·g)over CdS/N-TiO2 which was higher than that of CdS/TiO2.