Nanoscale. 2015 Jul 07;7(25):10982-8. doi: 10.1039/c5nr01204j. Epub 2015 Jun 09.

Dominant luminescence is not due to quantum confinement in molecular-sized silicon carbide nanocrystals.

Nanoscale

David Beke, Zsolt Szekrényes, Zsolt Czigány, Katalin Kamarás, Ádám Gali

PMID: 26055555 DOI: 10.1039/c5nr01204j

Abstract

Molecular-sized colloid silicon carbide (SiC) nanoparticles are very promising candidates to realize bioinert non-perturbative fluorescent nanoparticles for in vivo bioimaging. Furthermore, SiC nanoparticles with engineered vacancy-related emission centres may realize magneto-optical probes operating at nanoscale resolution. Understanding the nature of molecular-sized SiC nanoparticle emission is essential for further applications. Here we report an efficient and simple method to produce a relatively narrow size distribution of water soluble molecular-sized SiC nanoparticles. The tight control of their size distribution makes it possible to demonstrate a switching mechanism in the luminescence correlated with particle size. We show that molecular-sized SiC nanoparticles of 1-3 nm show a relatively strong and broad surface related luminescence whilst the larger ones exhibit a relatively weak band edge and structural defect luminescence with no evidence of quantum confinement effect.

Publication Types

• Journal Article
• Research Support, Non-U.S. Gov't