研究了MnOx活性层焙烧温度对Ti/SnO2+Sb2O3/MnOx电极性能的影响. 用XRD、SEM对电极活性层的结构、形貌进行了表征, 通过极化曲线和循环伏安曲线研究了电极在25℃1.0mol/L H2SO4溶液中的电催化活性, 并应用阳极快速寿命检测法测定了电极寿命. 结果表明: 焙烧温度为200℃时, 只有MnO2生成; 焙烧温度在300和400℃之间时, 同时有Mn2O3和MnO2晶体生成, 即在该温度范围内, Mn2O3和MnO2共存; 焙烧温度高于450℃时, 在实验条件下, 只有Mn2O3的衍射峰. 焙烧温度对电极电催化活性和电极寿命有显著的影响, Mn2O3和MnO2共存时电极具有较低的析氧电位. 焙烧温度为400℃时制备的电极电催化活性较高, 快速寿命检测法测得其电极寿命达39h, 具有良好的稳定性.
MnOx coatings deposited on a Ti/SnO2+Sb2O3 were prepared by the thermal decomposition of Mn(NO3)2. Surface morphology and microstructure of the coating were investigated by X-ray diffraction and scanning electron microscopy. The electrocatalytic activity of the anodes was assessed by polarization curves and voltammetric charge at 25C and 1.0mol/L in aqueous H2SO4, and accelerated life tests were performed at 60C and 1.0mol/L in aqueous H2SO4 with an anodic current density of 4.0A/cm2. The aim of this work was to prepare anodes based on ternary oxides showing high stability and electro-catalytic activity in acid solution. The XRD analysis reveals that MnO2 is formed at 200℃, after that, MnO2 and Mn2O3 coexist between 300℃ and 400℃ and above 450℃ main composition is Mn2O3. It is suggested that calcination temperatures affect the electro-catalytic activity and the lifetime of the anodes. The anode possesses relatively low overpotential, when the coexistence of
MnO2 and Mn2O3. The Ti/SnO2+Sb2O3/MnOx electrode, the MnOx coatings prepared at 400℃, exhibits excellent electrocatalytic activity and higher coating stability with accelerated life of 39h.
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