采用浸渍法和溶胶-凝胶法分别制备了含Mn中间层和SnO2表面催化层,并结合高温热氧化工艺制备了Ti/SnO2和Ti/MnOx/SnO2电催化电极.采用SEM、EDS和XPS等方法对两种电极进行了表征,使用大电流加速寿命实验详细研究了涂层的表面形貌、元素组成和化学态对两种电极稳定性的影响.结果表明:Ti/MnOx/SnO2电极的稳定性是Ti/SnO2电极的4.8倍,涂层使电极的稳定性显著提高.致密的涂层和较多的晶格氧能有效减少或阻止阳极的腐蚀,是电极稳定性提高的主要原因.
The interlayer containing Mn element and the SnO2 surface coating were prepared by dip coating and sol-gel method, respectively. The Ti/SnO2 and Ti/MnOx/SnO2 electrode were prepared by thermal oxidation technique. The service life of electrodes was evaluated by accelerated life experiment under big current density. The micrographs of electrode surface, the element composition of different layers and the chemical environment of elements in electrode surface were analyzed with the help of SEM, EDS and XPS. It was found that Ti/MnOx/SnO2 electrode processed longer service life than that of Ti/SnO2 electrode. The main reasons of long service life were compacted coating and much crystal oxygen in electrode surface which could reduce or resist the corrosion of electrode.