(Ni-Mo)TiO2纳米薄膜光催化降解刚果红的性能与机理.pdf

物理化学学报( Wuli Huaxue Xuebao
February
Acta Phys. -Chim. Sin. 2012, 28(2), 457-464
457
Article
doi:10.3866/PKU.WHXB20111208
www.whxb.pku.edu.cn
(Ni-Mo)/TiO2纳米薄膜光催化降解刚果红的性能与机理
李爱昌'李桂花郑琰冯玲玲郑彦俊
(廊坊师范学院化学与材料科学学院,河北廊坊065000
摘要:用恒电流复合电沉积方法制备(NI-Mo)TO2薄膜,以扫描电子显微镜(SEM)、X射线衍射(XRD)、拉曼
( Raman)光谱和紫外-可见漫反射光谱( JV-VIS DRS)对薄膜的表面形貌、晶相结构和光谱特性进行了表征,以
刚果红为模拟污染物对薄膜的光催化性能进行了测定,并讨论了刚果红溶液的H值对薄膜光催化活性的影
响.采用循环伏安技术和向溶液中加入活性物种捕获剂的方法对海膜光催化降解机理进行了探索.结果表明:
(NiMo)/TO2薄膜是由粒径为50-100nmTO2纳米粒子相和纳米晶NiMo固溶体相构成的复合溥膜.薄膜具
有较高的光催化活性,卤钨灯照射80min后,复合薄膜光催化刚果红的降解率是多孔TOo( Degussa P25
ITO(氧化個锡)纳米薄膜的2.43倍.(NiMo)/TO2薄膜光催化活性的提高主要归因于薄膜层中有效形成的
( NI-MO)/TO2异质结和良好的电子通道,以及NiMo纳米品合金对溶解氧和激发电子还原反应的催化作用.分
别给出了在紫外和可见光下薄膜光催化降解刚果红的反应机理
关键词:光催化;(N-Mo)TO2纳米膜;复合电沉积;刚果红;反应机理
中图分类号:O643
Photocatalytic Property and Reaction Mechanism of(ni-mo)/Tio2
Nano Thin Film Evaluated with Congo Red
LI Ai-chang
LI Gui-hua ZHENG Yan FENG Ling-ling ZHENG Yan-jun
(Paculty of Chemistry and Material Science, Langfang Teachers College, Langfang 065000, Hebei Province, PR. China)
Abstract: ( NI-MO)/TO composite thin films were prepared by composite electroplating at a constant
current. The surface morphology, phase structure, and optical characteristics of the thin films were
anal yzed by scanning electron microscopy( EM), X-a diaion(RD) Raman spectrum, and ul raviolet
visible diffuse reflectance spectroscopy(uv-vis DRS), respectively. The photocatalytic properties of the
(N-MOT1O composite thin films were evaluated with Congo red as a model compound. The effects of PH
of the Congo red aqueous solution on the photocatalytic activity of the(ni-mo/Tio2 thin films were
investiga ed. sin cyclic votammetry echnique and a me ho of adding active species scavengers to the
solution, the mechanisms of ptca alytic degradation of the films were explored. The results show that
the (N-MO io films consist of crystalline grains of TO in the size range of 50-100 nm and
nanocrystalline grains of Ni-mo in solid solution. The(Ni-mo)/ O films are photocatalytically more active
than a Tio /O (indium tin oxide) reference film. Under halogen light irradiation, the photocatalyti
degradation rate of the( Ni-mo io films is 2.43 times as much as that of a porous Tio2(Degussa P25
I O film. The improvement in photocatalytic activity for the composite films could be mainly attributed to the
heterojunction of ( - io the electronic passageway of Ni-mo in the composite films, and the
catalysis of N-MO in the composite film for the reaction of excited electrons with dissolved oxygen. The
photocatalytic reaction mechanisms of he(ni-motio films evaluated with Congo red are given under
visible and UV light irradiation, respectively
Received September 16 2011; Revised: November 27, 2011; Published on Web: December 8. 2011
CorrespondingauthorEmailaichangli@hotmail.com;Tel:+86-316-21972
The project was supported by the Science and Technology Projcct of Ilebei Province, China(11276732)
河北省科技支撵计划项目(11276732)资助
O Editorial office of Acta Physico-chimica Sinica