Direct Atomic Force Microscopic Determination of Surface Charge at the Gold/Electrolyte InterfaceThe Inadequacy of Classical GCS Theory in Describing the Double-Layer Charge Distribution
Direct Atomic Force Microscopic Determination of Surface Charge at the Gold/Electrolyte InterfaceThe Inadequacy of Classical GCS Theory in Describing the Double-Layer Charge Distribution
复制标题
金/电解质界面表面电荷的直接原子力显微测定经典GCS理论在描述双层电荷分布方面的不足
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
A. Bard
中科院分区：
文献类型：
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作者：
Jian Wang;A. Bard
利用原位原子力显微镜（AFM）测量了Au电极与KClO 4溶液界面处的表面电荷。通过处理AFM力曲线确定的有效电荷远小于电化学注入的有效电荷，有效/真实的表面电荷与电化学电荷的比率低于10%。这个巨大的差异表明，经典的Gouy-Chapman-Stern（GCS）理论不足以描述扩散的双电层。离子关联和离子凝聚效应可能是表面电荷减少的原因。关于含有二价物质[Ca（NO3）2和Na 2SO 4]的电解质的影响以及十二烷基硫酸钠在Au电极上的吸附的影响的额外实验为这种影响提供了额外的证据。
The surface charge at the interface of a Au electrode with a KClO4 solution was measured by in situ atomic force microscopy (AFM) using a modified cantilever with a charged SiO2 sphere. The effective charge determined by treating the AFM force curve was much smaller than that injected electrochemically, with the ratio of the effective/real surface charge to the electrochemical charge being below 10%. This large difference suggests that classical Gouy−Chapman−Stern (GCS) theory is inadequate to describe the diffuse electrical double layer. Ion correlation and ion condensation effects might account for the reduced surface charge. Additional experiments on the effect of electrolytes containing divalent species [Ca(NO3)2 and Na2SO4] and the effect of adsorption of sodium dodecyl sulfate on the Au electrode provide additional evidence for such effects.