Gas sensors made from ceramics utilize various principles for gas detection, particularly in aeronautic and space applications. The NASA Glenn Chemical Species Gas Sensors Team is advancing technology that detects gases like hydrogen, hydrocarbons, nitrogen oxides, carbon monoxide, oxygen, and carbon dioxide through microfabrication and MEMS technology, which enhances sensor miniaturization and efficiency. These sensors incorporate nanomaterials to improve performance and stability, along with temperature control features for consistent operation across varying conditions. Additionally, solid-state mixed potential electrochemical sensors employ differential electrocatalysis on different electrode materials, with response models based on Butler-Volmer kinetics and mass transport considerations. High-temperature ceramic gas sensors, developed by institutions like the Center for Industrial Sensors and Measurements at Ohio State University, focus on materials science to enhance selectivity and performance in industrial applications.