Studies of Nonstoichiometry, Transport, and Interface Characteristics of Pr(x)Ce(1-x)O(2-y) with Applications to Gas Sensors with Enhanced Selectivity

9701699 Tuller半导体气体传感器目前对特定类型的气体缺乏灵敏度和选择性，包括对汽车系统至关重要的碳氢化合物和氮氧化物。麻省理工学院的晶体物理和电陶瓷实验室与福特研究实验室联手探索了Pr-Ce-O体系，该体系表现出一系列吸引人的特征，适用于设计一种多功能的多组分化学传感器。这项拟议的研究将考察氧的组成、温度和分压之间的关系，以及非化学计量比、相稳定性和传输性质(电子和离子)之间的关系。要研究的关键特征是：(1)控制与费米能量位置相对应的n型和p型特征，以及相应的对各种HC和NOx分子的灵敏度和选择性；(2)化学扩散率对于“整体”性质的老化很重要；(3)与选择性和响应时间相关的表面反应动力学。基础项目研究将在麻省理工学院进行；传感器响应和特性研究将在福特研究实验室进行。该GOALI项目的参与者查看了他们对该项目成功所必需的材料、数据、模型和概念的反馈和交流。该项目由材料研究部的陶瓷项目和数学和物理科学局的多学科活动办公室联合资助。半导体气体传感器目前对特定类型的气体缺乏敏感性和选择性，包括对汽车系统至关重要的碳氢化合物和氮氧化物。麻省理工学院的晶体物理和电陶瓷实验室与福特研究实验室联手探索了Praseodyum-Ce-Ox系统，该系统具有许多吸引人的特性，可用于设计多功能多组分化学传感器。这项合作研究项目由材料研究部陶瓷项目和数学和物理科学局多学科活动办公室联合资助。***

9701699 Tuller Semiconducting gas sensors presently lack sensitivity and selectivity to specific types of gases including hydrocarbons and NOx important for automotive systems. The Crystal Physics and Electroceramics laboratory at M.I.T. and the Ford Research Laboratory have teamed up to explore the praseodymium-cerium- oxygen system that exhibits a number of features attractive for the design of a versatile multi-component chemical sensor. The proposed research will examine the relationships between composition, temperature and partial pressure of oxygen, as well as the nonstoichiometry, phase stability and transport properties (electronic and ionic). Key features to be studied are: (1) control of the n- and p-type character corresponding to the position of the Fermi energy and relevant sensitivity and selectivity to various HC and NOx molecules; (2) the chemical diffusivity important with respect to aging of the "bulk" properties; (3) surface reaction kinetics relevant to selectivity and response times. Fundamental project studies will be carried out at the Massachusetts Institute of Technology; sensor response and characterization studies are to be performed at Ford Research Labs. The participants of this GOALI project view their feedback and exchange on materials, data, models, and concepts essential to the success of this project. The project is jointly funded by the Ceramics Program of the Division of Materials Research and the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate. %%% Semiconducting gas sensors presently lack sensitivity and selectivity to specific types of gases including hydrocarbons and nitrogen oxides important for automotive systems. The Crystal Physics and Electroceramics laboratory at M.I.T. and the Ford Research Laboratory have teamed up to explore the praseodymium- cerium-oxygen system that exhibits a number of features attractive for the design of a versatile multi-component chem ical sensor. This collaborative research project is jointly funded by the Ceramics Program of the Division of Materials Research and the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate. ***