There is a high demand for miniaturized, low-power gas sensors that can be widely deployed in wireless applications for improved environmental protection, for public health, and for safe and efficient operation of many industrial processes. This proposal seeks to develop such sensors for the sensitive and selective detection of greenhouse gases, such as methane and carbon dioxide at ambient temperatures. Due to their relatively inert nature, greenhouse gases are extremely hard to detect at room temperature and hence at low power. More specifically, a transistor-based device will be developed employing a new class of porous material systems called metal-organic-frameworks. These novel chemicals will be engineered to bind selectively to the target gases. The broader impact of this work lies in its impact on other scientific fields, on society and in its educational and outreach activities. More broadly, insights will impact many disciplines and technologies using MOFs, such as gas separation and CO2 sequestration; proposed device designs have the potential to disrupt many sensing applications, such as workplace safety and air quality monitoring. Additional significant impact is on human resource development. The project will provide core training for graduate and undergraduate students who will benefit from interdisciplinary training at the crossroads of electrical engineering, surface chemistry, and materials science.
This proposal is centered on a new device architecture based on chemically gated field effect transistors, which can operate at room temperature, are compatible with integrated-circuit fabrication techniques, and can be rendered extremely selective by suitable functionalization of the chemically sensitive gate. Metal organic frameworks (MOFs) have been identified as the functional element for their demonstrated extreme selectivity to gaseous species. In particular, this proposal aims to demonstrate ultra-low power, chip-scale gas sensing of greenhouse gases. The intellectual merit of the proposed work lies both in the novel design architectures and in the selection of new materials for the dielectric and the chemically sensitive layers. From a fundamental point of view, the proposed research will allow understanding and predicting the factors affecting the growth of ultrathin MOFs, to achieve their integration in an electrical microdevices, and to optimize materials and designs for enhanced chemical sensing.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
