Gas Sensor Applications of Quantum Dots

At present, QDs are mainly used for cation detection and biosensing in solution-sensing assays (Costa-Fernandez 2006 Callan et al. 2007). However, it was established that the surrounding gas can also influence the fluorescence properties of QDs embedded in gas permeable polymer. In particular, Nazzal et al. (2003) found that the PL properties of the CdSe nanocrystals, stabilized by trioctylphos-phine oxide (TOPO) and incorporated in poly(methyl methacrylate) (PMMA) polymer films, can respond to the environment in a reversible and species-specific fashion (see Fig. 5.3). However, reversible response was observed in an oxygen-free atmosphere only. In oxygen, the CdSe was slowly oxidized, and therefore QDs have shorter lifetimes in air compared with those in an atmosphere of nitrogen. 

CdSe/ZnS Sol-gel silica matrix + amphiphilic polymer Qzone Saren et al. (2011) 

CdTe Poly(dimethyldiaUylammonium chloride) Formaldehyde Maetal. (2009) 

CdTe/CdS Sol-gel silica matrix+ PtFj TPP Qxygen Wang et al. (2008) 

InP Uncapped epitaxial InP QDs grown on InGaP layer Methanol De AngeUs et al. (2012) 

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