کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1668892 | 1008876 | 2011 | 7 صفحه PDF | دانلود رایگان |
Keggin-type dodecatungstosilicates polyoxometallates (POMs) ([SiW12O40]4−) were immobilized in a straightforward manner by electrostatic interactions on ammonium layers covalently grafted on silicon. This method does not require any POM modification synthetical steps. The presence of [SiW12O40]4− on the surface is demonstrated by X-ray Photoelectron Spectroscopy from a specific modification of the tungsten 4f7/2 signal. Moreover the surface coverage of [SiW12O40]4− has been improved by 35% upon changing the nature of the anchoring ammonium groups from protonated to methylated amino groups. The organic–inorganic composite films have also been characterized by cyclic voltammetry showing that POMs have a specific behavior on silicon surfaces. In addition the use of a polyallylamine capping layer proved to stabilize efficiently the POM electrochemical response.
Journal: Thin Solid Films - Volume 519, Issue 11, 31 March 2011, Pages 3732–3738