Insights from theory and simulation on the electrical double layer
Insights from theory and simulation on the electrical double layer
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DOI：
10.1039/b815946g
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发表时间：
2009-01-01
影响因子：
3.3
通讯作者：
Boda, Dezso
中科院分区：
文献类型：
--
作者：
Henderson, Douglas;Boda, Dezso
尽管在过去的几十年里，我们对双电层的概念理解已经取得了进步，但对实验和应用工作的解释仍然主要基于古伊、查普曼和斯特恩的古老的波松-玻尔兹曼理论。这是可以理解的，因为这个理论是简单和分析的。然而，由于忽略了离子/溶剂的原子/分子性质及其相互关系，因此它不是很准确。讨论了我们自己和其他人的仿真和一些理论研究，这些研究提高了我们的认识。这些研究表明，GCS理论预测了一个单调剖面的窄双层。这是不正确的。双层结构更宽，如果考虑到明显的溶剂分子，可能会有更明显的分层。多年来，双层的实验研究一直指向使用电化学作为分析工具。这对于分析化学研究是可以接受的。然而，对通常发生在电极表面的电化学反应的理解需要现代方法，模拟和理论表明，GCS理论可能存在重大误差。新的，基础的实验研究，将导致更深入的见解使用更新颖的系统是可取的。此外，生物物理学是一个有趣的领域。最近对离子通道的选择性和离子在蛋白质结合位点的吸附的研究表明，线性化的GCS理论有很大的误差。
Despite the fact that our conceptual understanding of the electrical double layer has advanced during the past few decades, the interpretation of experimental and applied work is still largely based on the venerable Poisson-Boltzmann theory of Gouy, Chapman and Stern. This is understandable since this theory is simple and analytic. However, it is not very accurate because the atomic/molecular nature of the ions/solvent and their correlations are ignored. Simulation and some theoretical studies by ourselves and others that have advanced our understanding are discussed. These studies show that the GCS theory predicts a narrow double layer with monotonic profiles. This is not correct. The double layer is wider, and there can be substantial layering that would be even more pronounced if explicit solvent molecules are considered. For many years, experimental studies of the double layer have been directed to the use of electrochemistry as an analytical tool. This is acceptable for analytic chemistry studies. However, the understanding of electrochemical reactions that typically occur at the electrode surface, where simulation and theory indicate that the GCS theory can have substantial errors, requires modern approaches. New, fundamental experimental studies that would lead to deeper insights using more novel systems would be desirable. Further, biophysics is an interesting field. Recent studies of the selectivity of ion channels and of the adsorption of ions in a binding sites of a protein have shown that the linearized GCS theory has substantial errors.