Tin-based oxides are attractive catalyst support materials considered for application in fuel cells and electrolysers. If properly doped, these oxides are relatively good conductors, assuring that ohmic drop in real applications is minimal. Corrosion of dopants, however, will lead to severe performance deterioration. The present work aims to investigate the potential dependent dissolution rates of indium tin oxide (ITO), fluorine doped tin oxide (FTO) and antimony doped tin oxide (ATO) in the broad potential window ranging from -0.6 to 3.2 V-RHE in 0.1 M H2SO4 electrolyte. It is shown that in the cathodic part of the studied potential window all oxides dissolve during the electrochemical reduction of the oxide - cathodic dissolution. In case an oxidation potential is applied to the reduced electrode, metal oxidation is accompanied with additional dissolution - anodic dissolution. Additional dissolution is observed during the oxygen evolution reaction. FTO withstands anodic conditions best, while little and strong dissolution is observed for ATO and ITO, respectively. In discussion of possible corrosion mechanisms, obtained dissolution onset potentials are correlated with existing thermodynamic data.
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机译:锡基氧化物是考虑用于燃料电池和电解槽的有吸引力的催化剂载体材料。如果适当地掺杂,这些氧化物是相对良好的导体,从而确保在实际应用中的欧姆降降至最低。但是,掺杂剂的腐蚀会导致性能严重下降。本工作旨在研究在0.1到-0.6至3.2 V-RHE的宽电位范围内,铟锡氧化物(ITO),氟掺杂锡氧化物(FTO)和锑掺杂锡氧化物(ATO)的电势依赖性溶出速率。 M H2SO4电解质。结果表明,在所研究的电位窗口的阴极部分,所有氧化物在氧化物的电化学还原过程中均会溶解-阴极溶解。如果将氧化电势施加到还原的电极上,则金属氧化会伴随额外的溶解-阳极溶解。在氧气逸出反应期间观察到额外的溶解。 FTO最能承受阳极条件,而ATO和ITO分别观察到很少和强烈的溶解。在讨论可能的腐蚀机理时,将获得的溶解开始电位与现有的热力学数据相关联。
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