Ion−Ion Correlation and Charge Reversal at Titrating Solid Interfaces
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- 作者：Christophe Labbez ; Bo Jnsson ; Michal Skarba ; Michal Borkovec
- 刊名：Langmuir
- 出版年：2009
- 出版时间：July 7, 2009
- 年：2009
- 卷：25
- 期：13
- 页码：7209-7213
- 全文大小：858K
- 年卷期：v.25,no.13(July 7, 2009)
- ISSN：1520-5827
文摘
Confronting grand canonical titration Monte Carlo simulations (MC) with recently published titration and charge reversal (CR) experiments on silica surfaces by Dove and Craven (Dove, P. M.; Craven, C. M. Geochim. Cosmochim. Acta 2005, 69, 4963−4970) and van der Heyden et al. (van der Heyden, F. H. J.; Stein, D.; Besteman, K.; Lemay, S. G.; Dekker, C. Phys. Rev. Lett. 2006, 96, 224502), we show that ion−ion correlations quantitatively explain why divalent counterions strongly promote surface charge which, in turn, eventually causes a CR. Titration and CR results from simulations and experiments are in excellent agreement without any fitting parameters. This is the first unambiguous evidence that ion−ion correlations are instrumental in the creation of highly charged surfaces and responsible for their CR. Finally, we show that charge correlations result in “anomalous” charge regulation in strongly coupled conditions in qualitative disagreement with its classical treatment.