摘要
利用微波辅助溶剂热法合成了In-Si共改性的TiO2光催化剂.粉末X射线衍射(XRD)、激光拉曼(Raman)光谱、N2吸脱附(BET)、X射线光电子能谱(XPS)、光致发光(PL)光谱和紫外-可见漫反射光谱(UV-Vis DRS)等实验表明,尽管掺杂和改性后TiO2结晶度略有降低,但不影响光催化剂锐钛相的形成.Si掺杂入TiO2晶格使颗粒变小,比表面积变大.In不能进入TiO2晶格,在TiO2表面形成了In2O3.罗丹明B(RhB)降解实验显示,In-Si共改性TiO2表现出很高的紫外和可见光催化活性,Si:In:Ti的摩尔比为0.03:0.02:1的样品(IST-2)光催化活性最高,紫外光下3 min即可将RhB降解完全,可见光下120 min RhB降解率为97%,这是由材料的高表面积,In2O3-TiO2复合半导体之间高效电荷转移及染料敏化等共同作用所致.对于苯酚,光催化降解则相对缓慢,700 min内尚不能降解完全.
In-Si comodified TiO2 photocatalysts were synthesized via a microwave-assisted solvothermal method. The obtained materials were characterized by X-ray diffraction （XRD）, Raman spectroscopy, N2 addesorption （BET）, X-ray photoelectron spectroscopy （XPS）, photoluminescence （PL） spectroscopy, and UV- Vis diffuse reflectance spectroscopy （UV-Vis DRS）. The photocatalysts all exist in an anatase phase, despite the fact that the crystallinity slightly decreased upon modification of the TiO2 photocatalysts. Simodification resulted in smaller nanoparticles and larger specific surface areas. Inmodification led to the formation of In203 on the surface of TiO2, such that In cannot enter the TiO2 lattice, contributing to efficient charge transfer between the coupled semiconductors In203 and TiO2. Degradation of Rhodamine B （RhB） showed that In-Si comodified TiO2 photocatalysts can exhibit high photocatalytic activity under both ultraviolet and visible light. The highest activity was obtained for In-Si comodified TiO2 with an Si：ln：Ti molar ratio of 0.03：0.02：1 （IST-2）, with which RhB was completely degraded within 3 min under ultraviolet light and where 97% of RhB was degraded after 120 min under visible light. The improved photocatalytic activity of In-Si comodified TiO2 may be ascribed to synergistic effects between large surface area, efficient electron transmission at the In203-TiO2 interface, and the dye sensation effect of RhB. Photodegradation for colorless phenol occurred at a much slower rate than that for RhB, and the phenol did not completely degrade within 700 min.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2014年第8期1543-1549,共7页
Acta Physico-Chimica Sinica
基金
山西省自然科学基金(2011011007-3)资助项目~~
