The adsorption of perchlorate, sulfate, selenate and water on Au(111)-textured electrodes from aqueous solutions: Simultaneous voltammetric, optical and microgravimetric studies
The adsorption of perchlorate, sulfate, selenate and water on Au(111)-textured electrodes from aqueous solutions: Simultaneous voltammetric, optical and microgravimetric studies
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Au(111) 纹理电极对水溶液中高氯酸盐、硫酸盐、硒酸盐和水的吸附：同时伏安、光学和微重量研究
DOI：
10.1016/j.electacta.2021.139107
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发表时间：
2021
影响因子：
6.6
通讯作者：
Scherson, Daniel
中科院分区：
文献类型：
--
作者：
Strobl, Jonathan R.;Scherson, Daniel
采用同步伏安法、垂直入射微分反射光谱法和电化学石英晶体微天平技术研究了高氯酸根Cl O 4 −（aq）、硫酸根SO 4 2 −（aq）和硒酸根Se O 4 2 −（aq）在Au（111）织构单晶上的吸附随外加电位E的变化。特别是，在纯0.1 M HClO 4或含有1 mM Na 2 SO 4或1 mM Na 2 SeO 4的相同电解质中收集的Δ R/R vs E数据可以通过使用本实验室早期报告的类似研究中引入的简单模型定量解释。该模型认为Δ R/R响应是由表面裸露区域和吸附物覆盖区域的贡献之和引起的，在每种情况下，它们都是所施加电势的线性函数。文献中Cl O 4 −（a q）和SO 4 2 −（a q）在Au（111）上的吸附等温线允许模型与在0.1 M HClO 4溶液中的1 mM Na 2 SO 4中获得的数据拟合。发现这两种含氧阴离子在很宽的电位范围内共吸附，当E> 1.25 V vs RHE时，SO 4 2 −（a q）完全取代Cl O 4 −（a q）。类似的Δ R/R测量包括在0.1 M HClO 4溶液中的1 mM Na 2 SeO 4，结合该模型，可以计算两种含氧阴离子的覆盖率作为E的函数。实验等温线使计算吸附的含氧阴离子的质量密度，ρ t h，产生的值几乎相同的那些来自EQCM实验，ρ exp，记录的数据范围ca。在所有三种溶液中，E <0.73 V vs RHE。然而，在较高的电位下，ρ exp显著大于光学测量预测的值，这一行为与水的共吸附一致。
The adsorption of perchlorate, C l O 4−(a q), sulfate, S O 4 2−(a q) and selenate, S e O 4 2−(a q) on Au (111)-textured single crystals from aqueous acidic solutions was examined as a function of the applied potential, E, by simultaneous voltammetry, normal incidence differential reflectance spectroscopy, ΔR/R, and electrochemical quartz crystal microbalance, EQCM, techniques. In particular, ΔR/R vs E data collected in pure 0.1 M HClO 4 or the same electrolyte containing either 1 mM Na 2 SO 4 or 1 mM Na 2 SeO 4 could be quantitatively accounted for by using a simple model introduced in similar studies reported earlier in this laboratory. This model regards the ΔR/R response as arising from a sum of contributions from bare and adsorbate covered areas of the surface, which are, in each case, linear functions of the applied potential. Adsorption isotherms for C l O 4−(a q), and S O 4 2−(a q) on Au (111) from the literature allowed fitting of the model to data obtained in 1 mM Na 2 SO 4 in 0.1 M HClO 4 solutions. The two oxyanions were found to co-adsorb over a wide potential range, with S O 4 2−(a q) fully displacing C l O 4−(a q) for E> 1.25 V vs RHE. Analogous ΔR/R measurements involving 1 mM Na 2 SeO 4 in 0.1 M HClO 4 solutions combined with the model allowed calculation of the coverage of the two oxyanions as a function of E. The experimental isotherms enabled calculation of the mass densities for the adsorbed oxyanions, ρ t h, yielding values virtually identical to those derived from EQCM experiments, ρ exp, for data recorded in the range ca. E< 0.73 V vs RHE in all three solutions. At higher potentials, however, ρ exp were significantly larger than those predicted by the optical measurements, a behavior consistent with water co-adsorption.