Fabrication of self-supporting porous silicon membranes and tuning transport properties by surface functionalization

Leonora Velleman, Cameron James Shearer, Amanda Vera Ellis, Dusan Losic, Nicolas Hans Voelcker, Joseph George Shapter

Research output: Contribution to journalArticleResearchpeer-review

35 Citations (Scopus)

Abstract

This study presents a simple approach to perform selective mass transport through freestanding porous silicon (pSi) membranes. pSi membranes were fabricated by the electrochemical etching of silicon to produce membranes with controlled structure and pore sizes close to molecular dimensions (∼12 nm in diameter). While these membranes are capable of size-exclusion based separations, chemically specific filtration remains a great challenge especially in the biomedical field. Herein, we investigate the transport properties of chemically functionalized pSi membranes. The membranes were functionalized using silanes (heptadecafluoro-1,1,2,2-tetrahydrodecyl)dimethylchlorosilane (PFDS) and N-(triethoxysilylpropyl)-o-polyethylene oxide urethane (PEGS) to give membranes hydrophobic (PFDS) and hydrophilic (PEGS) properties. The transport of probe dyes tris(2,2′-bipyridyl)dichlororuthenium(ii) hexahydrate (Rubpy) and Rose Bengal (RB) through these functionalized membranes was examined to determine the effect surface functionalization has on the selectivity and separation ability of pSi membranes. This study provides the basis for further investigation into more sophisticated surface functionalization and coupled with the biocompatibility of pSi will lead to new advances in membrane based bio-separations.

Original languageEnglish
Pages (from-to)1756-1761
Number of pages6
JournalNanoscale
Volume2
Issue number9
DOIs
Publication statusPublished - Sep 2010
Externally publishedYes

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