Bi2MoO6@CQDs/TiO2纳米管阵列的制备与光电催化性能

为提高TiO₂的可见光光电催化活性,本文用Bi₂MoO₆和碳量子点(CQDs)对TiO₂纳米管阵列(TNA)进行了改性。以CQDs、Bi(NO₃)₃·5H₂O和Na₂MoO₄为原料,通过简单的溶剂热法,在TNA中沉积了CQDs和Bi₂MoO₆,成功制备了新型Bi₂MoO₆@CQDs/TNA。扫描电镜(SEM)和元素mapping分析结果表明,CQDs和Bi₂MoO₆成功涂覆在TNA管壁上。通过在可见光下降解甲基橙(MO)溶液,评价了所制备的光催化剂的光电催化性能。结果显示,经3 h的光电催化降解,Bi₂MoO₆@CQDs/TNA对MO的去除率比Bi₂MoO₆/TNA高32%。CQDs优异的上转换光致发光(UCPL)性能促进了TiO₂在可见光下被激发产生光生载流子,同时Bi₂MoO₆与TiO₂的耦合抑制了光生载流子的复合,从而提高了Bi₂MoO₆@CQDs/TNA的光电催化活性。

Preparation and Photoelectrocatalytic Perfermance of Bi2MoO6@CQDs/TiO2 Nanotube Arrays

In this work, TiO₂ nanotube arrays (TNA) were modified through the incorporation of Bi₂MoO₆ and carbon quantum dots (CQDs), to improve the visible light photocatalytic activity of TiO₂. The CQDs, Bi(NO₃)₃·5H₂O, and Na₂MoO₄ were used as the starting materials, a facile solvothermal method was employed to fabricate the novel Bi₂MoO₆@CQDs/TNA composite through the deposition of CQDs and Bi₂MoO₆ into the TNA. Based on the SEM and elemental mapping results, CQD and Bi₂MoO₆ are successfully coated on the tube wall of TNA. Moreover, the photocatalytic performance of Bi₂MoO₆@CQDs/TNA composite was investigated through the degradation of methyorange (MO) solution under the visible light irradiation. The corresponding photoelelctrocatalytic test results confirm that the as-prepared Bi₂MoO₆@CQDs/TNA exhibits an enhanced photoelectrocatalytic activity. Bi₂MoO₆@CQDs/TNA has a 32% higher removal rate of MO than Bi₂MoO₆/TNA. The enhanced activity can be attributed to the excellent up-conversion photoluminescence (UCPL) of CQDs, promoting TiO₂ to generate photogenerated carriers under the visible light. Meanwhile, the heterojunction between Bi₂MoO₆ and TiO₂ can also effectively inhibit the recombination of photogenerated carriers.