Carbon dioxide gas sensors and method of manufacturing and using same

US8702962B1 · kind B1 · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• Gary W. Hunter · Oberlin, US
• Jennifer C. Xu · Westlake, US

Key dates

• Filing date: Aug 20, 2008
• Grant date: Apr 22, 2014
• Expiry date: Nov 28, 2031

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N33/004
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A gas sensor comprises a substrate layer; a pair of interdigitated metal electrodes, said electrodes include upper surfaces, the electrodes selected from the group consisting of Pt, Pd, Au, Ir, Ag, Ru, Rh, In, Os, and their alloys. A first layer of solid electrolyte staying in between electrode fingers and partially on said upper surfaces of said electrodes, said first layer selected from NASICON, LISICON, KSICON and β″-Alumina. A second layer of metal carbonate(s) as an auxiliary electrolyte engaging said upper surfaces of the electrodes and the first solid electrolyte. The metal carbonates selected from the group consisting of the following ions Na+, K+, Li+, Ag+, H+, Pb2+, Sr2+, Ba2+, and any combination thereof. An extra layer of metal oxide selected from the group consisting of SnO2, In2O3, TiO2, WO3, ZnO, Fe2O3, ITO, CdO, U3O8, Ta2O5, BaO, MoO2, MoO3, V2O5, Nb2O5, CuO, Cr2O3, La2O3, RuO3, RuO2, ReO2, ReO3, Ag2O, CoO, Cu2O, SnO, NiO, Pr2O3, BaO, PdO2, HfO3, HfO3 or other metal oxide and their mixtures residing above and in engagement with the second electrolyte to improve sensor performance and/or to reduce sensor heating power consumption.