Premium
How Ionic Polarization Affects Stern Potential: An Insight into Hofmeister Effects
Author(s) -
Liu Xinmin,
Ding Wuquan,
Tian Rui,
Li Rui,
Li Hang
Publication year - 2016
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj2016.04.0095
Subject(s) - stern , polarization (electrochemistry) , chemistry , ionic bonding , hofmeister series , chemical physics , coulomb , electric field , electric potential , ion , electron , physics , quantum mechanics , organic chemistry , engineering , marine engineering , voltage
Core Ideas A novel model is presented that estimates Stern potential at the solid–liquid interface. The strong polarization of ions is an important factor in Stern potential decrease. This strong polarization is an important origin of Hofmeister effects. The Stern potential of nano‐colloidal particles in aqueous solution has significant effects on chemical, physical, and biological processes. In this study, a modified theory for the Stern potential considering ionic polarization was established, and then the contributions of the ionic polarization to the Stern potential were quantified. The ionic polarization was strongly enhanced by the strong electric field from the surface charges of nano‐colloidal particles. The polarization energy (depending on the structure of the electron cloud) could even be comparable with the Coulomb energy; the ratio of polarization to Coulomb effect is 11.0% for Na + , 69.9% for K + , 34.0% for Mg 2+ and 103.4% for Ca 2+ . The ionic polarization at solid–liquid interfaces dramatically decreased the Stern potential. An important origin of Hofmeister effects was found and successfully verified by experiments.