SBIR-STTR Award

This Small Business Innovation Research (SBIR) Phase I project demonstrates the technical feasibility of a Fast-Response, High Sensitivity MEMS based NOx Emission Sensor for Diesel and Other Lean Burn Engines. The innovation combines the company?s SiC-based MEMS piezoelectric bimorph microresonator chemical detection technology with a NOx sensor materials technology patented by MIT, to develop a NOx sensor needed for emissions control and capable of operation in harsh engine emissions environments. This will be accomplished by 1) formulating NOx-sensitive material compositions optimized for sensitivity, reversibility and long term stability, 2) developing deposition processes for integrating the NOx sensitive materials onto its MEMS resonators, and 3) developing high temperature compatible electrodes and packaging compatible with hot engine emissions. If successful the proposed NOx sensor will fill a strategic and unmet need allowing diesel engines to conform to new diesel engine emissions standards being implemented by the U.S. Environmental Protection Agency (EPA), European Union and Japan. The proposed program will develop and demonstrate highly innovative, sensitive and stable MEMS-based resonator sensor suitable for detecting NOx and ultimately other pollutants in high temperature and chemically aggressive engine emissions environments, and will position US industry for a leadership role in engine emissions NOx control. In order to meet these standards, automobile and truck manufacturers have turned to two after-treatment technologies that reduce tailpipe NOx emission levels. Both after-treatment technologies require NOx sensors, to 1) control the after treatment trap-regenerate cycle, and 2) to monitor after-treatment system performance, confirming proper NOx restriction or triggering the ?check engine? indicator. The NOx sensor will allow clean, energy efficient diesel engines to continue to replace gasoline engines, thereby reducing fuel consumption and carbon emissions without increasing NOx pollutants. Furthermore, as the NOx sensor and NOx remediation technologies are introduced into diesel automobiles, trucks, locomotives, diesel power generators etc., these systems will become cleaner providing significant value to society in the form of cleaner air, improved health and reduced medical costs.

This Small Business Innovation Research (SBIR) Phase II project will develop a nitrogen oxide (NOx) sensor for diesel engine and other lean-burn combustion systems. This innovation combines unique SiC-based piezoelectric bimorph microresonator chemical detection technology with NOx sensitive materials, to develop an emissions control NOx sensor capable of operating in harsh engine emissions environments. The feasibility of the NOx sensor was demonstrated in Phase I by assembling a preliminary prototype, testing it in environments characteristic of hot engine emissions, and demonstrating 1 ppm NOx detection with 1 second response times and stable operation at 400?aC. The Phase II research objectives are to refine the sensor, including the bimorph resonator, NOx sensitive coatings, packaging and control electronics, to achieve higher temperature operation, 5 year lifetime, and reliable detection of 1 ppm NOx in the presence of varying concentrations of other exhaust gases. Extensive stability and life testing will be performed to identify and address potential degradation mechanisms such as poisoning, fouling, carbon deposition and materials inter diffusion. The prototype, including integrated heater, temperature sensor, control electronics and power/ data interface, will be operated in engine test stands to demonstrate performance in actual exhaust environments. The broader impact/commercial potential of this project lies in its ability to accelerate the adoption and use of automobiles that use clean diesel and renewable diesel fuels, which is a low-risk and high-impact way of reducing both polluting emissions and US dependency on foreign energy supplies. Diesel engines typically produce up to 20% less greenhouse gas emissions than a comparable gasoline powered vehicle. However, they also produce a significantly higher amount of nitrogen oxides (NOx), a pollutant that causes smog and acid rain. Although the technology exists to treat and eliminate this NOx pollution, it requires a high temperature compatible sensor with sensitivity and response time that does not exist commercially today. This NSF SBIR Phase II program will develop a NOx sensor capable of meeting the needs of the automotive industry for a diesel engine emissions sensor for both real-time on-board diagnostics and emissions reduction, bringing vehicles into compliance with new environmental regulations coming into effect in 2013. Enabling the wider adoption of clean diesel engines will reduce both greenhouse gas emissions and dependency on petroleum, as consumers increasingly choose these greener and more cost-effective vehicles