pH- and ionic strength-controlled cation permselectivity in amine-modified nanoporous opal films

被引：55

作者：

Newton, MR ^{[1
]}

Bohaty, AK ^{[1
]}

Zhang, YH ^{[1
]}

White, HS ^{[1
]}

Zharov, I ^{[1
]}

机构：

[1] Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA

来源：

LANGMUIR | 2006年 / 22卷 / 09期

关键词：

D O I：

10.1021/la053069z

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The influence of pH and ionic strength on permselective transport in nanoporous opal films prepared from 440 nm silica spheres was investigated by cyclic voltammetry in aqueous and acetonitrile solutions. Three-layer opal films were deposited from a 1.5 wt % colloidal solution of silica spheres onto 25-mu m-diameter Pt microdisk electrodes shrouded in glass. The films were chemically modified by immersing them in a dry acetonitrile solution of 3-aminopropyl triethoxysilane. When the surface amino groups of the modified opal films are protonated and there is little or no supporting electrolyte present in solution, the flux of cationic redox species through the opal membrane is blocked because of electrostatic repulsion. The permselectivity is pH-dependent and can be modulated by adjusting the Debye screening length within the nanopores of the opal by changing the ionic strength of the contacting solution.

引用

页码：4429 / 4432

页数：4

共 23 条

[21] Fabrication of two- and three-dimensional silica nanocolloidal particle arrays [J].