SBIR Phase I: Fast-Response, High Sensitivity MEMS based NOx Emission Sensor

该小型企业创新研究（SBIR）第一阶段项目展示了用于柴油和其他稀燃发动机的快速响应、高灵敏度MEMS NOx排放传感器的技术可行性。创新联合公司？的SiC基MEMS压电双晶片微谐振器化学检测技术与麻省理工学院专利的NOx传感器材料技术相结合，开发出排放控制所需的NOx传感器，能够在恶劣的发动机排放环境中工作。这将通过以下方式实现：1）配制针对灵敏度、可逆性和长期稳定性优化的NOx敏感材料组合物，2）开发用于将NOx敏感材料集成到其MEMS谐振器上的沉积工艺，以及3）开发与热发动机排放兼容的高温兼容电极和封装。如果成功的话，所提出的NOx传感器将填补一个战略性的和未满足的需求，使柴油发动机符合美国环境保护署（EPA），欧盟和日本正在实施的新柴油发动机排放标准。该计划将开发和展示高度创新、灵敏和稳定的MEMS谐振传感器，适用于检测高温和化学侵蚀性发动机排放环境中的NOx和其他污染物，并将使美国工业在发动机排放NOx控制方面发挥领导作用。为了满足这些标准，汽车和卡车制造商已经转向两种后处理技术，以降低排气管NOx排放水平。这两种后处理技术都需要NOx传感器，以1）控制后处理捕集器-再生循环，2）监测后处理系统性能，确认适当的NOx限制或触发？检查引擎？指标. NOx传感器将使清洁、节能的柴油发动机继续取代汽油发动机，从而在不增加NOx污染物的情况下减少燃料消耗和碳排放。此外，随着NOx传感器和NOx修复技术被引入柴油汽车、卡车、机车、柴油发电机等，这些系统将变得更清洁，为社会提供更清洁的空气、改善健康和降低医疗成本等重要价值。

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.