【作者】 冯俊；

【导师】 张敬东；

【作者基本信息】 华中科技大学 ， 分析化学， 2018， 硕士

【摘要】 光电催化技术是一种高效、绿色、可持续的高级氧化技术,其中光阳极材料的性能决定着光电催化效率。本文采用不同的方法制备了Bi VO4/Zn O、Bi2S3/Bi2O3/WO3光阳极薄膜材料,利用扫描电子显微镜、X射线衍射、X射线光电子能谱、荧光和紫外可见漫反射等多种手段对薄膜的结构、形貌、组分进行表征分析,对膜电极的光电催化性能研究。论文的主要研究内容如下:1采用液相沉积技术和连续离子层吸附技术成功地制备了Bi VO4/Zn O n-n异质结薄膜。通过对制备出的Bi VO4/Zn O薄膜的结构形貌分析,结果表明Zn O为纤锌矿结构的不规则纳米棒,Bi VO4为单斜晶结构的纳米颗粒。通过对Bi VO4/Zn O薄膜的光学性能分析,Bi VO4/Zn O具有更高的可见光利用效率。通过光电流、线性扫描伏安、阻抗测试表明Bi VO4/Zn O比单独的Zn O和Bi VO4具有更好的光电响应。通过降解四环素来评价Bi VO4/Zn O薄膜电极的光电催化性能。在可见光照射下,同时施加0.8V的电压,Bi VO4/Zn O异质结薄膜对20 mg/L四环素的降解效率2h内达到66.1%,分别比单独的Zn O、Bi VO4提高了40%、30.2%。通过自由基捕获实验证明了此光电催化体系中的反应主要活性物种为h+。2采用乙醇还原过氧化钨酸、旋涂和低温原位阴离子交换相结合成功地制备了Bi2S3Bi2O3/WO3异质结薄膜。通过荧光光谱、紫外可见-漫反射等证明Bi2S3/Bi2O3/WO3异质结薄膜比WO3、Bi2O3/WO3对可见光有更高的利用效率,对光生空穴和电子有更好的分离效率,对污染物有更高的降解效率。将此薄膜电极用于可见光光电催化降解罗丹明B(Rh B)和双氯芬酸钠。经过3h,Bi2S3/Bi2O3/WO3异质结薄膜对Rh B的脱色效率达到84.2%,对双氯酚酸钠的降解效率达到61.1%。更多还原

【Abstract】 Photoelectrocatalytic technique is an efficient,green and sustainable advanced oxidation processes.The efficiency of the photoelectrocatalytic system depends on the properties of anode materials.In this thesis,we employed different methods to prepare BiVO4/ZnO and Bi2S3/Bi2O3/WO3 film.SEM(Scanning electron microscopy),XRD(X-ray photoelectron spectroscopy),EDS(Element dispersive spectroscopy),XPS(X-ray photoelectron spectroscopy),PL(Photoluminescence)and UV-Vis DRS(UV-visible diffuse reflectance spectroscopy)to analysis the morphology,crystal,elementary compositions and the chemical valence states,photo-absorption performance of as-prepared materials.The photoelectrocatalytic performances of the as-prepared films were investigated.The main contents of paper are as follows:A BiVO4/ZnO composite film was successfully fabricated via a combination of the liquid phase deposition technique and the successive ionic layer adsorption and reaction process(SILAR).The crystalline phases and morphologies of materials were examined.The results revealed wurtzite ZnO were irregular nanorods and monoclinic BiVO4 irregular nanoparticles were successfully formed in the composite film.Photoluminescence analysis revealed that BiVO4/ZnO film showed superior response to pure ZnO and BiVO4 films.The photocurrent,linear sweep voltammetric(LSV)and electrochemical impedance spectroscopy(EIS)analyses suggested the BiVO4/ZnO film showed higher visible-light photoelectrocatalytic(PEC)activity than did pure ZnO and BiVO4 films.The PEC activity of BiVO4/ZnO film was evaluated by the the degradation of tetracycline.In the PEC system of removing contaminants,visible light irradiation and the applied voltage of +1.0 V were used,the 2-h removal efficiency of tetracycline reached 66.1%,which 40% and 30.2% higher than ZnO and BiVO4,respectively.The trapping experiments implied the main active species was h+.2.A Bi2S3/Bi2O3/WO3 heterojunction film was fabricated by combination of reduction of tungstic acid peroxide,spin-coating and in-situ anion exchange under room temperature.Photoluminescence and Uv-vis DRS analysis revealed Bi2S3/Bi2O3/WO3 heterojunction film showed greater utilization efficiency of visible light,better separation efficiency of photogenerated holes and electrons and higher removal efficiency of contaminants.The fabricated Bi2S3/Bi2O3/WO3 film was applied to the photoelectrocatalytic(PEC)degradation of diclofenac under visible light illumination.After 3h-treatment,the decoloration efficiency of Rh B was 84.2%,the removal efficiency of diclofenac was 61.1%.更多还原