摘要
采用水热法和溶胶凝胶法制备新型BiOCl/TiO2复合材料并明确了最优的掺杂比例(2%).随后利用X射线衍射(XRD)、紫外可见漫反射(DRS)、透射电镜(TEM)和X射线光电子能谱(XPS)对该材料进行表征.由于禁带宽度较大,纯BiOCl和TiO2的可见光催化性能极差,然而二者复合后,同条件下的苯降解率却大幅提升,可以达到40%以上.经证实,催化剂制备过程中,Bi的状态发生变化,在TiO2导、价带之间插入新的能级,使其禁带宽度变窄,电子可以实现可见光跃迁.
BiOCl / TiO2 is obtained via hydrothermal and sol-gel method with the optimal proportion of 2%. The compounds are characterized by X-ray diffraction( XRD),UV-Vis diffuse reflectance spectra( DRS) and transmission electron microscopy( TEM). The photocatalytic degradation towards gasphase benzene is over 40% under visible light irradiation,which is much better than pure TiO2 and BiOCl indivial. It`s proven that the status of Bi has changed during the preparation of BiOCl / TiO2,which may insert a new energy level between valence and conduction band of Bi OCl. As a result,electrons can be excited by visible light and jump to conduction band through the new band structure. Photo-carriers are then isolated on different sides of the heterojunction to reduce the recombination and the amount of generated *O2- and *OH free radicals increase significantly.
出处
《环境科学学报》
CAS
CSCD
北大核心
2015年第1期222-228,共7页
Acta Scientiae Circumstantiae
