The goal of this project is to develop methods of integrating metal nanoparticles and molecular imprinting techniques with organic electronics which will lead to the development of novel organic field effect transistor architectures for targeted detection of trace vapors of explosive molecules. Room temperature deposited, ultra-fine metal nanoparticles with tunable sizes (0.5 nm-2.5 nm) will be integrated with organic semiconductor materials such as vacuum-deposited poly-crystalline pentacene and solution-processed amorphous polymer (poly(2-methoxy-5-(3',7'-dimethyloctyloxy)-p-phenylene vinylene) (MDMO-PPV)) to fabricate floating gate electronic non-volatile memory-based sensing devices. A synergistic approach that combines these nano-scale elements into optimized organic field effect transistor structures is expected to yield new insights into these chemical interactions and provide better fundamental understanding of the sensing phenomena towards trace vapor sensing of explosives. Integration of such nanoparticles will also yield additional analyte-specific signatures in the transistor characteristics such that these signatures can improve the sensors?f discrimination capabilities. Selectivity of the organic field effect transistors will be addressed by developing and optimizing molecular imprinting techniques to give the transistors target-specific molecular recognition. Furthermore, organic field effect transistor sensor structures with varying channel lengths ranging from tens of microns to 5 nm will be explored to understand the diffusion kinetics of analytes and molecular level interaction through their single electron charge transfer characteristics with imprinted organic layers and metal nanoparticles.
Intellectual merit: A fundamental approach to understanding the molecular level interaction of the vapor phase explosive molecules with nano-engineered polymers and metal nanoparticles will advance research in the area of explosive sensing technologies. Studying the interaction of single molecules and the physico-chemical and electrical changes accompanying specific binding events will offer a plethora of information that can lead to improved sensing and monitoring capabilities which further leads to improved diagnostics, drug discovery and therapeutics. The library of interactions and specific recognition provided by these nano-engineered organic field effect transistors can be used for generation of information useful to quantify the presence, concentration and location of the explosive material in the environment that may be significantly hazardous.
Broader impact: This project will directly impact the technologies used for various explosive surveillance systems, and the technology can be translated to diagnostics for national security, public safety and the environment. A prominent educational component involves 'hands-on' educational activities in transformative sensor research and will specifically target students from groups traditionally underrepresented in science and engineering. These activities will involve secondary, graduate and undergraduate students, and the general public with the goal of broadening general knowledge about translational research in sensor systems.
