M(OH)3(M=In, Bi)基异质节光催化剂的组装、调控及作用机理研究

It is significant for investigation and development of nanomaterials to assemble and control compound nanomaterials by simple preparation method and explore interaction mechanism of the surface and interface between several components. In this project, we would assemble and control In(OH)3 and Bi(OH)3 by Rare earth doping and semiconduction composite, and study synthesis mechanism of In(OH)3 and Bi(OH)3-based heterostructure compound materials. The obtained products are characterized applying the technologies such as X-ray diffractometer, scanning electronic microscope, transmission electronic microscope, X-ray photoelectron spectrometer with ultraviolet photo-electron spectrometer and auger electron spectrometer, nanosize zeta potential meter, surface area analyzer. And then when different preparation methods are used, effects of molecular structure of reaction species and additives on the composition, structure, size and morphology of bulk phase and interface of the final products are discussed. In addition, the interaction and growth mechanism of various composites are explored under the different synthesis condition. Using the degradation of organic dye under visible light illumination as the probe reaction, the relationship between microstructures, morphologies of In(OH)3 and Bi(OH)3-based heterostructure compound photocatalysts and their degradation properties is studied. Furthermore, the action mechanism of the obtained compound photocatalysts with especial microstructure and properties strengthening migration of photogenerated electrons and holes during photocatalytic process is illustrated, which is to give the help of theory and technology for developing high effective photocatalysts.

利用简单的方法对复合纳米材料进行组装和调控，并探讨各组分在表面和界面间相互作用机制对纳米材料的研究和开发具有重要意义。本项目拟通过稀土掺杂和半导体复合的方式对In(OH)3和Bi(OH)3进行组装、调控，研究In(OH)3和Bi(OH)3基异质节复合材料的合成机理。利用XRD、SEM、TEM、XPS(带紫外光电子能谱和俄歇能谱)、纳米粒度电位仪、比表面和孔径分析仪等技术对产物进行表征，探讨不同制备方法下，反应物的分子结构及外加添加剂对反应及最终产物体相及界面组成、结构、尺寸和形貌的影响规律，探索不同制备过程中各组分间的相互作用和生长机制。拟以光催化降解有机染料为探针反应，研究In(OH)3和Bi(OH)3基异质节复合材料的微观结构、形貌与其降解性能之间的关系，阐明特定复合光催化剂对光催化过程中光生电子和空穴迁移增强的作用机制，为发展高效光催化剂提供理论和技术支持。

通过复合或掺杂发展了多种高效的铟基和铋基复合可见光催化剂，具体研究内容及结果如下：.1.制备了新型复合光催化剂ZnS/In(OH)3/In2S3，发现当原料ZnO/In/S=2:1:3(at.)，所制备的样品具有最佳的降解活性。RhB的官能团分别通过配位、静电吸附及氢键与催化剂表面相互作用，更有利于光生电子和空穴的快速迁移。.2.制备了新型异质结LaCO3OH/In(OH)3/In2S3，发现当La/In的摩尔分数为15%时，样品具有最高的降解RhB活性，与In(OH)3/In2S3相比，活性提高约一倍。同时催化剂具有较好的稳定性。•OH是重要的活性物种。.3.混合溶剂低温合成LaCO3OH/ZnIn2S4异质结，研究表明当La/In/Zn/=1:4:2(at.)，乙二醇/水=60:20（Vol.），80℃，处理4h时，样品活性最佳，同时具有较好的稳定性。活性物种主要包括h+、O2•－和•OH。在可见光下催化剂对甲基橙、四环素及孔雀石绿都有较好的降解效果。.4.铈掺杂制备了 Bi(OH)3 新型光催化剂，发现当Zn/Bi=0.02(at.)时，其速率常数为不掺杂Bi(OH)3的5倍。主要原因是Zn掺杂能改变催化剂的能带结构，提高光生载流子的转移速率，从而提高催化剂的降解效率。.5.铈+锌共掺杂制备了Bi2O3/Bi(OH)3复合物。实验表明当Ce和Zn的理论掺杂量分别为0.6 %和12%(摩尔分数）时，降解RhB时活性最佳。调节光催化过程中体系的酸碱性，当体系pH为2.5时，催化剂活性大大提高。.6.用三乙醇胺(TEOA)控制合成Bi24O31Br10/BiOBr 复合物光催化剂，发现当三乙醇胺(TEOA)的体积为 8 mL、Br/Bi(at.) =1.0时，可见光催化降解环丙沙星（CIP）活性最佳。反应速率常数为不加 TEOA 所得纯 BiOBr 的3.93倍。CIP主要官能团与催化剂表面通过静电吸引、与金属离子配位等紧密相互作用有利于界面电子和空穴的传递。.7.高活性的BiOCl 纳米片微结构调控，结果表明当TEOA/H2O(Vol)=1:3时，水热法制备的催化剂可见光催化降解CIP活性最佳。其降解速率常数为不加TEOA所得催化剂的14倍，是用NaOH和NH3•H2O分别代替TEOA调节到相同pH后所得催化剂的4倍。