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以TiO_2纳米管为模板,采用多组分自组装结合水热法制备Bi_2WO_6/TiO_2纳米管异质结构复合材料。通过多种技术如X射线衍射(XRD),X射线光电子能谱(XPS),N2吸附-脱附,扫描电镜(SEM),高分辨透射电镜(HRTEM)和紫外可见漫反射吸收光谱(UV-Vis DRS)考察所制备样品的组成、结构、形貌、光吸收和电子性质。Bi_2WO_6纳米片或纳米粒子分布在TiO_2纳米管上,形成异质结构。随后,通过在紫外、可见和微波辅助光催化模式下降解染料罗丹明B(Rh B)来评价复合催化剂的光催化活性。与TiO_2纳米管和Bi_2WO_6相比,Bi_2WO_6/TiO_2-35纳米管在多模式下表现出更优异的光催化活性。与紫外和可见降解模式相比,Bi_2WO_6/TiO_2-35纳米管在微波辅助光催化模式下对Rh B的降解效率最高。这种增强的光催化活性源于适量Bi_2WO_6的引入、纳米管独特的形貌特征和降解模式所引起的增强的量子效率。降解过程中的活性物种被证明是h+,·OH和·O2-自由基。而且,在微波辅助光催化模式下,可产生更多的·OH和·O2-自由基。
TiO 2 nanotubes were used as template to prepare Bi 2 WO 6 / TiO 2 nanotube heterostructures by multi-component self-assembly combined with hydrothermal method. The microstructure and mechanical properties were characterized by a variety of techniques such as XRD, XPS, N2 adsorption-desorption, SEM, HRTEM and UV- Vis DRS) to investigate the composition, structure, morphology, light absorption and electronic properties of the prepared samples. Bi_2WO_6 nanosheets or nanoparticles are distributed on TiO_2 nanotubes to form heterostructures. Subsequently, the photocatalytic activity of the composite catalyst was evaluated by degradation of the dye rhodamine B (Rh B) in an ultraviolet, visible and microwave assisted photocatalytic mode. Compared with TiO_2 nanotubes and Bi_2WO_6, Bi_2WO_6 / TiO_2-35 nanotubes showed more excellent photocatalytic activity in multi-mode. Bi2WO_6 / TiO_2-35 nanotubes had the highest degradation efficiency of Rh B under microwave-assisted photocatalysis compared with UV and visible degradation modes. This enhanced photocatalytic activity is due to the introduction of the appropriate amount of Bi 2 WO 6, the unique topographical features of the nanotubes, and the enhanced quantum efficiency caused by the degradation mode. The active species in the degradation process proved to be h +, · OH and · O2-radicals. Moreover, in microwave-assisted photocatalytic mode, more · OH and · O2-radicals can be produced.