{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T03:15:57Z","timestamp":1774494957712,"version":"3.50.1"},"reference-count":54,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2009,5,6]],"date-time":"2009-05-06T00:00:00Z","timestamp":1241568000000},"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>Current production and emerging NOx sensors based on optical and nanomaterials technologies are reviewed. In view of their potential applications in mechatronics, we compared the performance of: i) Quantum cascade lasers (QCL) based photoacoustic (PA) systems; ii) gold nanoparticles as catalytically active materials in field-effect transistor (FET) sensors, and iii) functionalized III-V semiconductor based devices. QCL-based PA sensors for NOx show a detection limit in the sub part-per-million range and are characterized by high selectivity and compact set-up. Electrochemically synthesized gold-nanoparticle FET sensors are able to monitor NOx in a concentration range from 50 to 200 parts per million and are suitable for miniaturization. Porphyrin-functionalized III-V semiconductor materials can be used for the fabrication of a reliable NOx sensor platform characterized by high conductivity, corrosion resistance, and strong surface state coupling.<\/jats:p>","DOI":"10.3390\/s90503337","type":"journal-article","created":{"date-parts":[[2009,5,6]],"date-time":"2009-05-06T12:56:49Z","timestamp":1241614609000},"page":"3337-3356","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Optical and Electronic NOx Sensors for Applications in Mechatronics"],"prefix":"10.3390","volume":"9","author":[{"given":"Cinzia","family":"Di Franco","sequence":"first","affiliation":[{"name":"CNR-INFM Regional Laboratory LIT3, via Amendola 173, 70126 Bari, Italy"}]},{"given":"Angela","family":"Elia","sequence":"additional","affiliation":[{"name":"CNR-INFM Regional Laboratory LIT3, via Amendola 173, 70126 Bari, Italy"},{"name":"Physics Department, University of Bari, Via Amendola 173, I-70126 Bari, Italy"}]},{"given":"Vincenzo","family":"Spagnolo","sequence":"additional","affiliation":[{"name":"CNR-INFM Regional Laboratory LIT3, via Amendola 173, 70126 Bari, Italy"},{"name":"Physics Department, Politecnico di Bari, Via Amendola 173, I-70126 Bari, Italy"}]},{"given":"Gaetano","family":"Scamarcio","sequence":"additional","affiliation":[{"name":"CNR-INFM Regional Laboratory LIT3, via Amendola 173, 70126 Bari, Italy"},{"name":"Physics Department, University of Bari, Via Amendola 173, I-70126 Bari, Italy"}]},{"given":"Pietro Mario","family":"Lugar\u00e0","sequence":"additional","affiliation":[{"name":"CNR-INFM Regional Laboratory LIT3, via Amendola 173, 70126 Bari, Italy"},{"name":"Physics Department, University of Bari, Via Amendola 173, I-70126 Bari, Italy"}]},{"given":"Eliana","family":"Ieva","sequence":"additional","affiliation":[{"name":"Chemistry Department, University of Bari, via Orabona 4, 70126, Bari, Italy"}]},{"given":"Nicola","family":"Cioffi","sequence":"additional","affiliation":[{"name":"Chemistry Department, University of Bari, via Orabona 4, 70126, Bari, Italy"}]},{"given":"Luisa","family":"Torsi","sequence":"additional","affiliation":[{"name":"Chemistry Department, University of Bari, via Orabona 4, 70126, Bari, Italy"}]},{"given":"Giovanni","family":"Bruno","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Methodologies and of Plasmas, IMIP-CNR, via Orabona 4, 70126, Bari, Italy"}]},{"given":"Maria","family":"Losurdo","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Methodologies and of Plasmas, IMIP-CNR, via Orabona 4, 70126, Bari, Italy"},{"name":"Duke University, Department of Electrical and Computer Engineering, Durham, NC 27708, USA"}]},{"given":"Michael A.","family":"Garcia","sequence":"additional","affiliation":[{"name":"Duke University, Department of Electrical and Computer Engineering, Durham, NC 27708, USA"}]},{"given":"Scott D.","family":"Wolter","sequence":"additional","affiliation":[{"name":"Duke University, Department of Electrical and Computer Engineering, Durham, NC 27708, USA"}]},{"given":"April","family":"Brown","sequence":"additional","affiliation":[{"name":"Duke University, Department of Electrical and Computer Engineering, Durham, NC 27708, USA"}]},{"given":"Mario","family":"Ricco","sequence":"additional","affiliation":[{"name":"ISI Consulting, via Brunelleschi 15, 70010 Casamassima (BA), Italy"}]}],"member":"1968","published-online":{"date-parts":[[2009,5,6]]},"reference":[{"key":"ref_1","unstructured":"National Ambient Air Quality Standards Available online: http:\/\/www.epa.gov\/air\/criteria.html. 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