SnO2-NiO-IrO2/Ti的制备及电催化氧化甲基橙溶液的研究

Study on the Electrocatalytic Oxidation of Methyl Orange Solution by the SnO2-NiO-IrO2/Ti electrode

摘要:

因SnO2-NiO特殊的异质结结构，被用作气敏材料和超级电容器电极添加材料，在电催化氧化污水方面研究较少。本文通过添加活性氧化物IrO2提高其导电性来研究SnO2-NiO-IrO2电极电催化甲基橙溶液的效果。热分解法制备不同IrO2含量的Ti/SnO2-NiO-IrO2电极，采用X射线衍射(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)、比表面(BET)、循环伏安法(CV)、交流阻抗谱法(EIS)、极化曲线(LSV)、总有机碳(TOC)、紫外可见光谱(UV)、强化寿命等方法系统研究Ti/SnO2-NiO-IrO2电极的电催化性能。结果表明：IrO2改变SnO2晶格中氧空位的浓度，使SnO2晶体结构中产生杂质缺陷，细化晶粒，进而增大复合氧化物涂层的比表面积和导电性，提高活性自由基向内层扩散的速度，从而优化电极的催化活性和稳定性。IrO2掺杂量为23.1%的电极对甲基橙具有最好的降解效果。IrO2掺杂量为23.1%时，电极对甲基橙具有最高降解率为93%，电解反应累加时间最高可达678 h。

Abstract:

Because of the special heterojunction structure, SnO2-NiO has been used as gas sensing material and supercapacitor electrode addition material.But it has been studied less in electrocatalytic oxidation of industrial wastewater. The effect of SnO2-NiO-IrO2 electrode on the electrocatalytic methyl orange solution was studied by adding active oxide IrO2. SnO2-NiO-IrO2/Ti electrodes were prepared by thermal decomposition method. SEM, XRD, XPS, BET, CV, EIS, LSV, TOC, UV, and strongthen life were used to test the microstructure and the catalytic performance.It’s shown that IrO2 changeg the concentration of oxygen vacancies in the SnO2 lattice, resulting in forming the impurity defects in the crystal structure, refining the grains, and then increasing the specific surface area and conductivity of the composite oxide coatings. The diffusion rate of the active matter to the inner layer was increased too. Thus, the catalytic activity and stability of the electrode were optimized.The electrode with IrO2 content of 23.1% had the best degradation effect on methyl orange, which had a maximum degradation rate of 93% and a maximum service life of 678 hs.