铜锡合金阳极在熔融碳酸盐中氧化膜的形成及其防护性能

Corrosion Performance of Oxide Scales on Bronze QSn7-0.2 Anode in Molten Carbonates

通过动电位扫描阳极氧化成膜、恒电位预氧化成膜以及开路电位浸泡预氧化成膜3种途径分别得到了3种氧化膜各有差异的QSn7-0.2铜锡合金电极。采用光学显微分析与XRD测试,表征了各氧化膜的形貌和成分,并且利用阳极极化曲线研究了3种成膜电极在450℃Li-Na-K三元共晶熔融碳酸盐中作为惰性析氧阳极的可行性。结果表明,恒电位预氧化成膜以及开路电位浸泡预氧化成膜两种成膜方法均能够在QSn7-0.2铜锡合金阳极表面形成含SnO_2的氧化膜,该膜能够显著阻碍基体合金中Cu的阳极溶解腐蚀,并且对析氧反应具有确定的电催化性能。

Three different oxide scales on the surface of bronze QSn7-0.2 electrodes were prepared in Li-Na-K eutectic molten carbonates at 450℃ via potentiodynamic polarization,potentiostatic polarization by 0.2 V and simple immersion by open circuit potential respectively,then were characterized by means of optical microscopy and X-ray diffractometer（XRD）.While the feasibility of which as potential inert anode for electrochemical transformation of CO2 was assessed in the melt by electrochemical method.The result shows that besides Cu2O and CuO,SnO2 is detected in the oxide scales of the bronze QSn7-0.2 electrodes oxidized via potentiostatic polarization by 0.2 V and simple immersion by open circuit potential.The oxide scales with SnO2 can significantly prevent the bronze QSn7-0.2 anodes from corrosion and act also as electro-catalyzer for the oxygen evolution.