Durability and photophysical properties of surfactant-covered porous silicon particles in aqueous suspensions

✍ Scribed by Balaguer, M. ;Pastor, E. ;Bychto, L. ;Atienzar, P. ;Miranda, M. A. ;Matveeva, E. ;Chirvony, V. S.

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 237 KB
• Volume: 205
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200780173

✦ Synopsis

Abstract

With the aim to impart hydrophilic properties to porous silicon (PSi) containing luminescent Si nanocrystals the PSi surface has been modified by a non‐ionic surfactant (undecylenic acid) either physically (by physisorption) or chemically (through Si‐C bond). PSi luminescence spectra and reversible quenching of the luminescence by molecular oxygen have been studied as a function of time elapsed after PSi surface immersion in water. The data obtained indicate that Si nanocrystal surface oxidation, which is realized in water, is accompanied by an appearance of a new type of luminescence centres, which are quenched by molecular oxygen differently than free excitons. SiO‐related surface states are suggested to be responsible for the observed effect. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)