Here is the abstract you requested from the IMAPS_2012 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Synergistic opto-electronic sensing platform based on zinc oxide semiconducting nanopackage|
|Keywords: zinc oxide nanowire, opto-electronic sensor, unmanned platform|
|Ultra-trace detection of hazardous chemicals using functionalized nanopackages is a rapidly emerging field. Development of cost-effective synthesis techniques concomitant with novel packaging methodologies has expanded the breadth of applications utilizing nanostructures for different sensing applications. Zinc oxide nanostructures have garnered tremendous attention due to their excellent optical and electrical properties at nanoscale. In this work, we report synthesis of hierarchical zinc oxide nanowires through a chemical vapor deposition process on insulating sapphire substrate and their subsequent integration into a sensing platform. Subsequent growth, morphology and crystal structure of synthesized nanowires was confirmed through SEM, TEM and x-ray diffraction studies. Surface composition and local bonding environment was determined through XPS, Raman and Fourier-transform infrared spectroscopy techniques. Photoluminescence characteristics of pristine nanowires indicated defect-free nanowires suitable for device fabrication. Subsequently, the nanowire surface was functionalized with an optically active receptor compound which is used to detect traces of p-nitrophenol vapors (analyte) through a fluorescence quenching process. The sensing mechanism of the receptor was validated independently through fluorescence studies and detection limit of 28 ppb is reported. Furthermore, optical quenching involves transfer of electrons and zinc oxide nanowires serve as an excellent supporting backbone facilitating modulation of carrier concentration. Hence, electrical characteristics of functionalized- and non-functionalized zinc oxide nanowires-based ohmic device were determined through Agilent semiconductor parameter analyzer. Utilization of optical and electronic properties of zinc oxide nanowires in conjunction can lead to sensitive and selective detection of hazardous chemicals while concurrently mitigating false positives rates. Based on preliminary findings a generic design incorporating miniaturized sensing unit and opto-electronic back-end electronics suitable for field deployment is presented. This would facilitate development of unmanned systems capable of providing remote detection of hazardous chemicals by transferring detected signals over wireless communication channel.|
The University of Alabama-Tuscaloosa