A Mechanistic Study of Dissolution of Pt-Fe Binary Alloys in 0.5 M H2SO4 Solution by Channel Flow Triple Electrode
A Mechanistic Study of Dissolution of Pt-Fe Binary Alloys in 0.5 M H2SO4 Solution by Channel Flow Triple Electrode
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通道流三电极溶解 Pt-Fe 二元合金在 0.5 M H2SO4 溶液中的机理研究
DOI：
10.1149/2.0551704jes
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发表时间：
2017
影响因子：
3.9
通讯作者：
and Atsushi Nishikata
中科院分区：
文献类型：
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作者：
Azusa Ooi. Eiji Tada;and Atsushi Nishikata
在298 K、0.5MH2SO4介质中，采用通道流三电极（CFTE）对Pt-50at%Fe（Pt-50 Fe）和Pt-25at%Fe（Pt-25 Fe）溶液中的Fe（II）和Fe（III）离子以及Pt（II）和Pt（IV）离子进行了原位检测。这些离子，从设置在通道上游的Pt-Fe合金工作电极溶解，同时检测两个Au集电极放置在下游通过还原或氧化其溶解的离子。当Pt-50 Fe在0.05 ~ 1.4 V（相对于标准氢电极）之间进行电位循环时，在双层充电区（0.25-0.85 V），Fe的溶解显著增强，这可能是由于Pt原子的表面扩散。此外，Fe溶解被Pt溶解增强，Pt溶解发生在位置交换电位区域（1.2-1.4 V）和阴极扫描中Pt氧化物的还原电位（0.9-0.5 V）中。相反，当Pt-25 Fe在0.05和1.4 V之间进行电位循环时，Fe溶解被Pt富集层强烈抑制，特别是在DL的电位区域。溶解也依赖于上限的电位循环（E U）和显着抑制，即使是Pt-50 Fe，当E U为0.6 V。
A channel flow triple electrode (CFTE) was applied for the in situ detection of Fe ions (Fe (II) and Fe (III)) and Pt ions (Pt (II) and Pt (IV)) dissolved from Pt–50at% Fe (Pt–50Fe) and Pt–25at% Fe (Pt–25Fe), under potential cycling in 0.5 MH 2 SO 4 at 298 K. These ions, dissolved from a Pt–Fe alloy working electrode set upstream in a channel, were simultaneously detected on two Au collector electrodes placed downstream by reducing or oxidizing their dissolved ions. When Pt–50Fe was potential-cycled between 0.05 and 1.4 V vs. standard hydrogen electrode, Fe dissolution was significantly enhanced in a double-layer (DL) charging region (0.25–0.85 V), probably owing to the surface diffusion of Pt atoms. In addition, the Fe dissolution was enhanced by Pt dissolution which takes place in a place-exchange potential region (1.2–1.4 V) and in the reduction potential of Pt oxides (0.9–0.5 V) in the cathodic scan. On the contrary, when Pt–25Fe was potential-cycled between 0.05 and 1.4 V, Fe dissolution was strongly suppressed by a Pt–enriched layer, especially in the potential region for the DL. The dissolution also depended on the upper limit of potential cycling (E U) and was significantly suppressed, even for Pt–50Fe, when E U was 0.6 V.