In collaboration with the Petrukhina Research Group

QD based sensing materials have the ability to provide multiple levels of sensing selectivity as a result of a tailored design of both their host matrix and the QD itself for a specified sensing application. The development of tailored QD sensing materials requires both an understanding of the PL dependence both at baseline conditions and upon exposure to the target molecules. In our work on designing tailored QD materials for sensing applications we have utilized stabilizing (trioctyl phosphine oxide (TOPO) and stearic acid (SA)) ligands along with surface activating groups such as (benzoic acid (BA) and pentafluorobenzoic acid (FBA)) which were attached to the surface of the CdSe quantum dots. With this approach we have achieved a detection limit of 15ppm and 50 ppm for xylenes and toluene in air. A factor of ~3 selectivity enhancement for xylenes over toluene is a demonstration of the effectiveness in the tailored design approach utilized in the quantum dot sensing program.