Diagnosis on improved electrocatalytic activity of La2Ni0.8Cu0.2O4+delta electrodes towards oxygen reduction reaction
Diagnosis on improved electrocatalytic activity of La2Ni0.8Cu0.2O4+delta electrodes towards oxygen reduction reaction
复制标题
La2Ni0.8Cu0.2O4 δ电极对氧还原反应电催化活性提高的诊断
DOI：
10.1016/j.apsusc.2017.06.238
复制
发表时间：
2017
影响因子：
6.7
通讯作者：
Kim Bok-Hee
中科院分区：
文献类型：
--
作者：
Wang Ya-Ping;Xu Qing;Huang Duan-Ping;Zhao Kai;Chen Min;Kim Bok-Hee
采用丝网印刷技术在Ce0.8Sm0.2O1.9电解液上制备了不同厚度的La2Ni0.8Cu0.2O4+δ电极。研究了La2Ni0.8Cu0.2O4+δ电极对氧还原反应的电催化活性，并与La2NiO4+δ电极进行了比较。用X射线光电子能谱技术分析了La2NiO4+δ和La2Ni0.8Cu0.2O4+δ表面组成元素的化学状态，以了解两种电极的电催化活性。在920℃烧结的La2Ni0.8Cu0.2O4+δ电极表现出比文献报道的更高温度(例如1200℃)烧结的电极更好的电催化活性。在La_2NiO_4+δ中掺入铜可以有效地提高电催化活性。La2Ni0.8Cu0.2O4+δ电极的电催化活性与其厚度有关。对于厚度为10μm的电极，获得了最佳的电催化活性，在800℃下的极化电阻为0.13Ωcm2。结果表明，La2Ni0.8Cu0.2O4+δ电极的电催化活性是由分子氧在表面的解离吸附过程决定的。
La2Ni0.8Cu0.2O4+δelectrodes with different thicknesses were prepared on Ce0.8Sm0.2O1.9electrolyte using screen printing technique. The electrocatalytic activity of La2Ni0.8Cu0.2O4+δelectrodes towards oxygen reduction reaction was investigated in comparison with La2NiO4+δelectrode. To understand the electrocatalytic activity of the two electrodes, chemical states of constituent elements on the surface of La2NiO4+δand La2Ni0.8Cu0.2O4+δwere analyzed using X-ray photoelectron spectroscopy technique. La2Ni0.8Cu0.2O4+δelectrodes sintered at 920 °C exhibited improved electrocatalytic activity relative to literature results of the electrodes sintered at higher temperatures (e.g. 1200 °C). The Cu doping in La2NiO4+δwas validated to be effective in enhancing electrocatalytic activity. The electrocatalytic activity of La2Ni0.8Cu0.2O4+δelectrodes was found to be dependent on their thickness. Optimal electrocatalytic activity was achieved for the electrode with a thickness of 10 μm, showing a polarization resistance of 0.13 Ω cm2at 800 °C. The effects of Cu doping and electrode thickness were diagnosed with respect to contributions of involved electrode reaction steps. The results of this work underscore that the electrocatalytic activity of La2Ni0.8Cu0.2O4+δelectrodes is dictated by dissociative adsorption process of molecular oxygen on the surface.