Surface Modification of Erbium-Doped Silicon Nanocrystals

This work describes a viable route to the surface chemical modification of erbium-doped silicon nanocrystals via their reaction with a capping reagent immediately after their formation in a pyrolysis oven. While the derivatized, doped nanocrystals retain the desired luminescence at 1540 nm associated with the erbium centers, for the −SiMe3- and −Si(CH2)3CN-capped nanocrystals, there is a clear improvement in their solubility in solvents such as butylphenyl ether. In contrast, propylamine-modified surfaces become less soluble in the solvents tested, presumably as a consequence of extensive hydrogen-bonding-induced aggregation. The implications of these modified nanocrystals for other applications are also discussed.