新型Ti/Al复合基体对传统Ti基PbO2电极性能的改善

Improvements on Properties of Traditional Ti-based Lead Dioxide Electrodes by Novel Ti/Al Composited Substrate Electrodes

摘要:

对比研究新型Ti/Al复合基体电极Ti/Al/Ti/SnO2+Sb2O4/PbO2和传统纯Ti基体电极Ti/SnO2+Sb2O4/PbO2的性能差异。通过改变Ti/Al复合基体的制备温度，探索制备新型电极的最佳工艺条件。运用SEM、EDS和XRD表征Ti/Al基体界面层与电极表面β-PbO2活性层的物相形貌。结合电化学测试技术，分析基体制备温度对电极电化学性能及寿命的影响。结果表明：Ti/Al复合基体的电阻率仅为纯Ti的1/10,该电极β-PbO2层的晶粒趋于细化且均匀，活性层比表面积增大，电化学性能均好于纯Ti基体电极。其中，在540 ℃获得的Ti/Al基体复合界面相为TiAl3，该复合基体电极的性能最佳。电极电阻较纯Ti基体电极降低43%，极化电位下降18%，在0.2 A/cm2的电流密度下，电位降低了320 mV。经强极化测试，该电极具有最大的交换电流密度j0与最低的析氧超电压η，工业使用寿命长达10.4年，高出传统电极50%，具有良好的应用前景

Abstract:

The comparison studies on performance differences between traditional Ti-based electrode of Ti/SnO2+Sb2O4/PbO2 and novel Ti/Al composited substrate electrode of Ti/Al/Ti/SnO2+Sb2O4/PbO2 were provided. Through changing the sintering temperature of Ti/Al composited substrate, the optimum process conditions for preparing this novel electrode were obtained. The structure and morphology of Ti/Al bonding interface layers and active surface β-PbO2 coatings were characterized by SEM, EDS and XRD. Combined with electrochemical testing technology, the effect of sintering temperature on electrochemical properties and lifetime was analyzed. The results show that this novel Ti/Al composited substrate electrode, whose electrical resistivity is only one tenth of pure Ti substrate, exhibits a smaller grain size, larger surface active areas and better electrochemical properties compared to pure Ti-based electrode. Intermetallic of TiAl3 in Ti/Al composite interface is obtained at the sintering temperature of 540 °C, and it exhibits the best performance. The polarization resistance and polarization potential of Ti/Al composited substrate electrodes decline by 43% and 18%, respectively. The potential decreases by 320 mV compared to Ti-based electrode under the condition of 0.2 A/cm2 current density. This electrode has the best exchange-current density j0 and the lowest oxygen overvoltage η by strong polarization measurement. And the industrial service lifetime of this novel electrode reaches 10.4 years, 50% higher than that of traditional Ti-based electrodes