The objective of this research is to reveal the basic mechanisms by which nanoelectronic devices can sense gas molecules, and to explore procedures for improving the performance of such nanosensors. The conductance of nanowires (e.g., nanotubes, nanoribbons, etc.) can change drastically upon the adsorption of gas molecules. This conductance modulation can be a basis for efficient gas sensing. Attributing the results of nanosensing experiments to a combination of possible mechanisms, such as charge transfer and dipole interactions, is complicated. Theoretical/computational models can therefore provide essential insight on the science of gas sensing by nanoelectronic devices.
Intellectual merit: Using accurate ab initio computer simulations and quantum transport calculations, this research seeks to clarify the roles of possible conductance modulation mechanisms. The research incorporates temperature effects so as to make meaningful comparisons with experiments possible. In addition to simple nanowires, other possible candidates for improved sensing performance are also considered. These include functionalized and gated nanowires, as well as nanowires under mechanical stress.
Broader impacts: The methodology of this project concerns the general mechanisms underlying the performance of nanoelectronic devices. Understanding the roles of functionalization, impurities, mechanical deformations, and temperature effects on transport through nanoelectronic devices is invaluable towards their realistic characterization and design. The project especially targets underrepresented students and potential students through regular precollege demonstrations and outreach programs. Special web-based presentations, using attractive computer simulation snapshots and clips, make the basic principles, outcomes, and benefits of nanoelectronic-based gas sensors accessible to the general public.
