The rapid formation of functional monolayers on silicon under mild conditions

Authors

Simone Ciampi, University of New South WalesFollow
Erwann Luais, University Of New South Wales
Michael James, Australian Synchrotron
Moinul H. Choudhury, University of New South Wales
Nadim A. Darwish, University of New South Wales
J Justin Gooding, University of New South Wales

RIS ID

89624

Publication Details

Ciampi, S., Luais, E., James, M., Choudhury, M. H., Darwish, N. A. & Gooding, J. Justin. (2014). The rapid formation of functional monolayers on silicon under mild conditions. Physical Chemistry Chemical Physics, 16 (17), 8003-8011.

Abstract

We report on an exceedingly mild chemical functionalization of hydrogen-terminated Si(100) with unactivated and unprotected bifunctional α,ω-dialkynes. Monolayer formation occurs rapidly in the dark, and at room temperature, from dilute solutions of an aromatic-conjugated acetylene. The method addresses the poor reactivity of p-type substrates under mild conditions. We suggest the importance of several factors, including an optimal orientation for electron transfer between the adsorbate and the Si surface, conjugation of the acetylenic function with a π-system, as well as the choice of a solvent system that favors electron transfer and screens Coulombic interactions between surface holes and electrons. The passivated Si(100) electrode is amenable to further functionalization and shown to be a viable model system for redox studies at non-oxide semiconductor electrodes in aqueous solutions.