{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T19:23:09Z","timestamp":1774552989171,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,6]],"date-time":"2019-09-06T00:00:00Z","timestamp":1567728000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Detection of carbon dioxide (CO2) is very important for environmental, health, safety and space applications. We have studied novel multiwall carbon nanotubes (MWCNTs) and an iron oxide (Fe2O3) nanocomposite based chemiresistive sensor for detection of CO2 at room temperature. The sensor has been miniaturized to a chip size (1 cm \u00d7 2 cm). Good sensing performance was observed with a wide detection range of CO2 concentrations (100\u20136000 ppm). Structural properties of the sensing materials were characterized using Field-Emission Scanning Electron Microscopy, Fourier-Transform Infrared and Raman spectroscopies. The greatly improved sensitivity of the composite materials to CO2 can be attributed to the formation of a depletion layer at the p-n junction in an MWCNT\/iron oxide heterostructure, and new CO2 gas molecules adhere to the high surface area of MWCNTs due to the concentration gradient. The test results showed that the CO2 sensor possesses fast response, compact size, ultra-low power consumption, high sensitivity and wide dynamic detection range.<\/jats:p>","DOI":"10.3390\/s19183848","type":"journal-article","created":{"date-parts":[[2019,9,6]],"date-time":"2019-09-06T02:59:22Z","timestamp":1567738762000},"page":"3848","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Solid State Electronic Sensors for Detection of Carbon Dioxide"],"prefix":"10.3390","volume":"19","author":[{"given":"Ami","family":"Hannon","sequence":"first","affiliation":[{"name":"KBR Wyle Inc. at NASA Ames Research Center, CA 94035, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"NASA Ames Research Center, CA 94035, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1186\/s12245-017-0142-y","article-title":"Carbon dioxide poisoning: A literature review of an often forgotten cause of intoxication in the emergency department","volume":"10","author":"Permentier","year":"2017","journal-title":"Int. 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