铬掺杂TiO_2液相沉积膜可见光下降解甲基橙研究  

Visible Light Degradation of Methyl Orange Using Liquid Phase Deposition TiO_2 Film Doped with Cr

作　　者：龚建宇[1] 张敬东[2] 濮文虹[1] 杨昌柱[1] 

机构地区：[1]华中科技大学环境科学与工程学院 [2]华中科技大学化学与化工学院,湖北武汉430074

出　　处：《环境科学与技术》2011年第10期35-38,共4页Environmental Science & Technology

基　　金：国家自然科学基金资助(20977037)

摘　　要：实验用液相沉积法制备铬掺杂改性的二氧化钛（Cr-TiO）2薄膜电极,并在可见光下利用制备的电极对甲基橙溶液（MO）进行光电降解实验研究。并对制备的薄膜进行光电流（I-t）、交流阻抗（EIS）和Mott-Schottky等电化学相关表征。当掺杂浓度为0.2%时,薄膜电极具有最好的光电催化活性。在以0.2%Cr-TiO2薄膜电极对甲基橙（MO）降解的实验中,系统研究了膜电极对甲基橙溶液的光电催化降解效果。结果表明：铬掺杂改性的0.2%Cr-TiO2电极,分别在提供可见光、外加正偏压1 V、同时提供可见光和外加1 V电压的三种条件下,对浓度为5 mg/L MO的降解2 h后效果分别为9.4%、23.8%、51.7%。当MO的初始浓度为1 mg/L时,其光电催化2 h后效果达到75.2%;当改变MO的初始pH值时,其最大降解效率发生在pH为3~4时,达到70.2%。Chromium doped titanium dioxide（Cr-TiO2）thin film electrodes prepared by liquid phase deposition were used to degrade methyl orange（MO） under visible light with photoelectrochemical method.The films were characterized by electrochemical methods such as I-t,EIS and Mott-Schottky.It was found that Cr-doped TiO2 showed good photoelectrocatalytic activity and the added content of 0.2% film electrode was the best one.Cr-TiO2 film electrodes were used to degrade MO under visible light illumination.Some factors influencing the photocatalytic degradation of MO on Cr-TiO2 electrode were systematically investigated.Results showed that the degradation efficiency for 5 mg/L MO reached 9.4%,23.8% and 51.7% after 2 h treatment with 0.2% Cr-TiO2 under visible light,applying 1 V bias potential and both visible light and applying 1 V bias potential respectively.The visible light degradation efficiency for 1 mg/L MO reached up to 75.2% and for pH range at 3~4 reached up to 70.2%.

关 键 词：液相沉积 铬掺杂 可见光 氧化钛 甲基橙 

分 类 号：X131.2[环境科学与工程—环境科学]