Understanding the Influence of the Electrochemical Behavior of Potassium Hexacyanoferrate(II/III) on Acetonitrile/Water Binary Mixtures: An Experimental and Molecular Dynamics Study
Understanding the Influence of the Electrochemical Behavior of Potassium Hexacyanoferrate(II/III) on Acetonitrile/Water Binary Mixtures: An Experimental and Molecular Dynamics Study
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DOI：
10.1021/acs.jpcc.7b10989
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发表时间：
2018-01
影响因子：
3.7
通讯作者：
F. F. Batista-F.;L. Siqueira;Luciano T. Costa;T. L. Ferreira
中科院分区：
文献类型：
--
作者：
F. F. Batista-F.;L. Siqueira;Luciano T. Costa;T. L. Ferreira
采用微电极伏安法获得的信息，在乙腈/水二元混合物中的六氰合铁（II/III）酸钾的行为，以了解混合物的本体性质和电极/二元溶液的界面性质。所获得的数据的第一次分析表明，六氰合铁（III）的扩散系数值显然不尊重斯托克斯-爱因斯坦方程，考虑到流体动力学半径不随乙腈含量而变化。另一个有趣的观察是吸附的电生成的六氰合铁（II）酸钾的电极表面上的二元混合物与50摩尔%的乙腈或更高。分子动力学模拟表明，乙腈分子积累的电极模型的表面上，也是离子物种往往形成集群在乙腈丰富的混合物。由于六氰合铁酸钾不溶于乙腈，铁络合物在电极上的吸附是可逆的。
Microelectrode voltammetry was employed to gain information on the behavior of potassium hexacyanoferrate(II/III) in acetonitrile/water binary mixtures in order to understand the bulk properties of the mixture and the electrode/binary solution interface properties. The first analysis of the obtained data demonstrated that the diffusion coefficient values of hexacyanoferrate(III) apparently do not respect the Stokes–Einstein equation, considering the hydrodynamic radius does not change with acetonitrile content. Another interesting observation is the adsorption of electrogenerated potassium hexacyanoferrate(II) onto the electrode surface in binary mixtures with 50 mol % acetonitrile or higher. Molecular dynamics simulations showed that acetonitrile molecules accumulate on the surface of an electrode model and also that ionic species tend to form clusters in acetonitrile-rich mixtures. Since potassium hexacyanoferrate(II) is not soluble in acetonitrile, the adsorption of the iron complex onto the electrode ...