热处理对SnO2/Ti电化学催化降解p-苯醌的影响

用热分解方法制备了钛基二氧化锡阳极(SnO₂/Ti),对比研究了空气/氧气2种热处理气氛对电极性能的影响.用扫描电镜(SEM)观察了电极表面形貌,对电极表面主要膜元素的化学状态进行了X射线光电子能谱(XPS)分析,对电极在不同溶液的动电位极化行为进行了测试,研究了2种电极在5mA/cm²恒电流状态下对p-苯醌的电解催化去除性能.SEM观察表明,2种电极表面都为典型的泥裂形貌,但在氧气气氛中退火处理的电极具有更大的活性表面积.XPS分析发现,在氧气气氛中退火处理的电极表面Sn3d_5/2、Sb3d_5/2电子的结合能较在空气气氛中退火处理的低0.15eV.动电位极化测试结果与恒电流电解实验结果都表明,在氧气气氛中退火处理的电极对水中p-苯醌具有更好的电化学催化去除性能.在电解进行至溶液完全脱色的情况下,氧气气氛中退火处理的电极对水中TOC的去除率为76.3%,而空气气氛中退火处理的电极对水中TOC的去除率为63.3%.在2种电极条件下,溶液中TOC浓度随电解时间的变化规律均符合指数变化规律.

Effect of Heat Treatment on the Electrocatalytic Activity of SnO2/Ti Anode in Degradation of p-Benzoquinone

Sb-doped SnO₂/Ti anode was prepared in our lab with thermal decomposition method,and in the same time, the effect of heat treatment on the properties of the electrode also was studied. Scanning electron microscopy (SEM) was used to study the surface characterization of the electrodes. X-ray photoelectro-spectroscopy (XPS) measurements were carried out to study the chemical state of elements, Sn and Sb. The potentiodynamic polarization behaviors of the two anodes in different solutions were performed. Galvanostatic electrolyses were carried out at 5mA/cm² to study the electrocatalytic activity of the two anodes in removing organic pollutant. SEM showed that the electrodes had the same well-known cracked-mud structure, while the electrode annealed in O₂ SnO₂/Ti(O₂)] had more larger surface area than the electrode annealed in the air SnO₂/Ti(air)]. XPS measurements showed that the binding energies of both Sn3d_5/2 and Sb3d_5/2 of SnO₂/Ti(O₂) were 0.15eV smaller than what of the SnO₂/Ti(air) film. Both of the electrochemical measurements and electrolyses results confirmed that SnO₂/Ti(O₂) was more active in the degradation of organic pollutant. The galvanostatic electrolyses were lasted until the solutions were decoloured throughly, 76.3% of total organic carbon (TOC) was removed with SnO₂/Ti(O₂), compared with 63.3% of SnO₂/Ti(air). The similar exponential rules were driven for the variations of residual TOC concentration with two anodes.