Abstract
The fabrication of a novel CO2 sensitive silane-based matrix and the proof of its concept will be presented in this thesis. New hydrophobic sol-gel matrices were developed for direct encapsulation of the trioctylphosphine(TOPO)capped hydrophobic CdSe/ZnS quantum dots (QD), and the co-encapsulation of a new ion-pair consisting of m-Cresol Purple (CP) and Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (ODAC-tMOS). A new internal buffer, Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium hydroxide (ODAOH-tMOS), was also employed to increase the structural stability of the sensor matrix. The development of the new matrices and the preparation of the new quaternary ammonium hydroxideand ion-pair will be discussed, as will existing analogue systems present in the literature. Further, encapsulation of quantum dots in silica stabilized micelles will also be discussed, as well as the attempted co-encapsulation of dye-quaternary ammonium ion-pairs. The spectral shifts of the dyes and the quantum dots encapsulated in matrices and nanoparticles have been investigated, as has the response of the sensor when exposed to dissolved CO2.