Piasecki Wojciech
Group for Theoretical Problems of Adsorption, Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30-239 Kraków, Poland.
J Colloid Interface Sci. 2006 Oct 15;302(2):389-95. doi: 10.1016/j.jcis.2006.06.039. Epub 2006 Aug 14.
Prior knowledge of the model parameters describing the metal oxide/simple electrolyte interface is frequently crucial to successful application of surface complexation modeling. On the basis of the parameter values for the 2-pK triple-layer model recently published by Sverjensky, the parameters for the 1-pK TLM were determined. This was done by fitting (using the 1-pK model) the proton surface charge and ion adsorption isotherms generated by the 2-pK TLM. It was assumed that inner-layer capacitance was the same for both models. A strong correlation was found between ion adsorption constants of different electrolytes on the same oxide predicted by both models. Additionally, the 1-pK and 2-pK models predict different electrokinetic potentials in spite of very similar values of calculated surface charge and ion adsorption isotherms when the same value of outer-layer capacitance is assumed. Because the value of outer-layer capacitance practically does not influence surface charge and electrolyte adsorption isotherms, it can be treated as a freely adjusted parameter, the value of which can be estimated if we have measured the electrokinetic potential.
了解描述金属氧化物/简单电解质界面的模型参数对于成功应用表面络合模型通常至关重要。基于Sverjensky最近发表的2-pK三层模型的参数值，确定了1-pK TLM的参数。这是通过（使用1-pK模型）拟合由2-pK TLM生成的质子表面电荷和离子吸附等温线来完成的。假设两个模型的内层电容相同。发现两个模型预测的相同氧化物上不同电解质的离子吸附常数之间存在很强的相关性。此外，尽管假设外层电容值相同时计算出的表面电荷和离子吸附等温线的值非常相似，但1-pK和2-pK模型预测的电动电位不同。由于外层电容值实际上不影响表面电荷和电解质吸附等温线，因此可以将其视为一个可自由调整的参数，如果我们测量了电动电位，就可以估计其值。
