{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T02:50:58Z","timestamp":1771901458653,"version":"3.50.1"},"reference-count":110,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2009,6,15]],"date-time":"2009-06-15T00:00:00Z","timestamp":1245024000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we review our recent results in developing gas sensors for hydrogen using various device structures, including ZnO nanowires and GaN High Electron Mobility Transistors (HEMTs). ZnO nanowires are particularly interesting because they have a large surface area to volume ratio, which will improve sensitivity, and because they operate at low current levels, will have low power requirements in a sensor module. GaN-based devices offer the advantage of the HEMT structure, high temperature operation, and simple integration with existing fabrication technology and sensing systems. Improvements in sensitivity, recoverability, and reliability are presented. Also reported are demonstrations of detection of other gases, including CO2 and C2H4 using functionalized GaN HEMTs. This is critical for the development of lab-on-a-chip type systems and can provide a significant advance towards a market-ready sensor application.<\/jats:p>","DOI":"10.3390\/s90604669","type":"journal-article","created":{"date-parts":[[2009,6,16]],"date-time":"2009-06-16T02:11:38Z","timestamp":1245118298000},"page":"4669-4694","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":90,"title":["Advances in Hydrogen, Carbon Dioxide, and Hydrocarbon Gas Sensor Technology Using GaN and ZnO-Based Devices"],"prefix":"10.3390","volume":"9","author":[{"given":"Travis","family":"Anderson","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fan","family":"Ren","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stephen","family":"Pearton","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Byoung Sam","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hung-Ta","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chih-Yang","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jenshan","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Florida \/ Gainesville, FL 32611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2009,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1049\/el:20030107","article-title":"9.2W\/mm (13.8W) AlGaN\/GaN HEMTs at 10 GHz and 55 V drain bias","volume":"39","author":"Zhang","year":"2003","journal-title":"Electron. 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