电子束辐照制备Pd/TiO2光催化薄膜

用电子束辐照浸泡在浓度分别为1×10-5、1×10-4、1×10-3、1×10-2和1×10-1mol/L的PdCl2溶液中的TiO2薄膜,在TiO2薄膜表面形成Pd纳米颗粒.通过X射线衍射(X-ray diffractometry,XRD)、场发射扫描电镜(Field emission scanning electron microscope,FESEM)、X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)和紫外可见(Ultraviolet visible,UV-Vis)吸收光谱对辐照后的Pd/TiO2薄膜进行表征.分析表明,TiO2薄膜表面上沉积了直径20-50 nm的颗粒,为面心立方结晶的金属Pd;Pd/TiO2薄膜的UV-Vis光谱吸收边向可见光方向发生了偏移.用甲基橙作为光催化降解反应物,研究了Pd/TiO2薄膜分别在紫外光、可见光作用下的光催化降解效率.结果表明,Pd/TiO2薄膜的光催化能力显著地提高,在紫外光、可见光作用下的光催化效率分别提高了2.25倍和3.4倍.

Preparation of Pd/TiO2 photocatalytic films by electron beam irradiation

TiO2 films immerging in PdCl2 solution with PdCl2] concentration at 10-5, 10-4, 10-3, 10-2 and 10-1 mol/L respectively were irradiated by electron beam in order to deposit nano-cluster noble metal Pd. The irradiated films were characterized by XRD, XPS, FMSEM and UV-visible spectrometry. The results show that the Pd clusters with fcc crystal structure were 20-50 nm in diameter on the surface of TiO2 films. Red shift was found in the absorp-tion spectrum of modified Pd/TiO2 films. The photocatalytic capability of the films were tested by degradation of methyl orange (MO) in aqueous solutions under both UV and visible light illumination. The photocatalytic experi-ments showed that the photocatalytic ability of Pd/TiO2 under both UV and visible light irradiation could be improved dramatically.