Novel photoluminescence properties of surface-modified nanocrystalline zinc oxide: toward a reactive scaffold.

Nanocrystalline zinc oxide has been functionalized with 11-triethoxysilylundecal to introduce chemical reactivity for subsequent molecular attachment while preserving its unique photoluminescence (PL) properties. Silane bonding is confirmed using FTIR and photoelectron spectroscopy, with a total Si concentration of 3 to 4 atomic %. PL measurements demonstrate a 2-fold enhancement of its UV peak and maintenance of its visible peak compared to control samples. Enhancement of the UV peak is likely due to a decrease in the surface-dependent nonradiative recombination process. These results lay the framework for sensor fabrication, with the aldehyde groups available to bind analytes that would alter the PL spectrum.