高等学校化学学报 ›› 2015, Vol. 36 ›› Issue (3): 551.doi: 10.7503/cjcu20140694

• 物理化学 • 上一篇    下一篇

BiOCl/NaBiO3复合材料的原位合成及光催化性能

姬磊(), 于瑞敏, 王浩人, 陈丽铎, 汪怀远   

  1. 东北石油大学化学化工学院, 石油与天然气化工黑龙江省高校重点实验室, 大庆 163318
  • 收稿日期:2014-07-24 出版日期:2015-03-10 发布日期:2015-02-04
  • 作者简介:联系人简介: 姬 磊, 女, 博士, 副教授, 主要从事光催化材料的制备和表征, 光催化机理研究. E-mail: jileiwipm@163.com
  • 基金资助:
    黑龙江省普通高等学校青年学术骨干支持计划(批准号: 1251G002)资助

In-situ Synthesis of BiOCl/NaBiO3 Composites and Their Photocatalytic Activities

JI Lei*(), YU Ruimin, WANG Haoren, CHEN Liduo, WANG Huaiyuan   

  1. Provincial Key Laboratory of Oil and Gas Chemical Technology, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing 163318, China
  • Received:2014-07-24 Online:2015-03-10 Published:2015-02-04
  • Contact: JI Lei E-mail:jileiwipm@163.com

摘要:

利用HCl与NaBiO3反应原位制备了结构可控的BiOCl/NaBiO3复合光催化材料. 通过X射线粉末衍射(XRD)、 紫外-可见漫反射光谱(UV-Vis-DRS)和扫描电子显微镜(SEM)等技术对其晶相组成、 光吸收特性和表面形貌进行了表征, 并评价了样品在可见光和紫外光下的光催化性能. 结果表明, 尽管BiOCl几乎没有可见光活性, 但27.4%BiOCl/NaBiO3在可见光下却表现出明显高于纯BiOCl和NaBiO3的光催化活性. 由于紫外光照可以有效激发BiOCl, 所有组成的复合BiOCl/NaBiO3都显示出高于纯BiOCl和NaBiO3的光催化活性, 其中47.6%BiOCl/NaBiO3具有最大光催化活性. 研究了加入不同活性物种的捕获剂对光催化效率的影响, 结合荧光实验结果和样品能带结构推测了复合材料光催化过程中光生载流子的传输行为. 结果表明, BiOCl/NaBiO3催化活性增强主要归结于2种材料之间形成了有效的异质结构, 其内建电场能够促进光生载流子的传输和分离; 羟基自由基在光催化降解过程中是主要的活性物种.

关键词: 光催化, BiOCl, NaBiO3, 复合材料, 机理

Abstract:

BiOCl/NaBiO3 composite photocatalytic materials were in-situ synthesized through the reaction of NaBiO3 and HCl. The phase structures, surface morphologies and optical properties of the samples were studied by X-ray powder diffraction(XRD), scanning electron microscope(SEM) and UV-Vis diffuse reflectance spectra(UV-Vis DRS), respectively. The photocatalytic activities of the samples were evaluated by degradation of rhodamine B(RhB) under visible and ultraviolet light, respectively. Under visible light the 27.4%(molar fraction) BiOCl/NaBiO3 shows higher photocatalytic activity than the pure BiOCl and NaBiO3; under ultraviolet light all the BiOCl/NaBiO3 composites show higher photocatalytic activities than pure BiOCl and NaBiO3. The results indicate that the composition of BiOCl and NaBiO3 can form heterojunction region, and then influence the transfer behavior of photogenerated carriers. The photocatalysis experiments with different trapping agents and terephthalic acid photoluminescence(TA-PL) suggest that ·OH played major role for RhB degradation. A possible mechanism involving charge separation process between BiOCl and NaBiO3 was proposed. The n-p type heterojunction at the interface between p-BiOCl and n-NaBiO3 can efficiently reduce the recombination of photogenerated electron-hole pairs, which accounts for the enhancement of photocatalytic activity. From the analysis of potential, it is theoretically deduced that the photocatalytic degradation of RhB could be attributed to the ·OH and hole rather than ·O2- radicals.

Key words: Photocatalysis, BiOCl, NaBiO3, Composite, Mechanism

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