{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T19:53:08Z","timestamp":1774036388725,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,11]],"date-time":"2019-09-11T00:00:00Z","timestamp":1568160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2018R1A2A1A05023126"],"award-info":[{"award-number":["2018R1A2A1A05023126"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Nanocomposite structures, where the Fe, Fe2O3, or Ni2O3 nanoparticles with thin carbon layers are distributed among a single-wall carbon nanotube (SWCNT) network, are architectured using the co-arc discharge method. A synergistic effect between the nanoparticles and SWCNT is achieved with the composite structures, leading to the enhanced sensing response in ammonia detection. Thorough studies about the correlation between the electric properties and sensing performance confirm the independent operation of the receptor and transducer in the sensor structure by nanoparticles and SWCNT, respectively. Nanoparticles with a large specific surface area provide adsorption sites for the NH3 gas molecules, whereas hole carriers are supplied by the SWCNT to complete the chemisorption process. A new chemo-resistive sensor concept and its operating mechanism is proposed in our work. Furthermore, the separated receptor and transducer sensor scheme allows us more freedom in the design of sensor materials and structures, thereby enabling the design of high-performance gas sensors.<\/jats:p>","DOI":"10.3390\/s19183915","type":"journal-article","created":{"date-parts":[[2019,9,11]],"date-time":"2019-09-11T11:26:34Z","timestamp":1568201194000},"page":"3915","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["A Separated Receptor\/Transducer Scheme as Strategy to Enhance the Gas Sensing Performance Using Hematite\u2013Carbon Nanotube Composite"],"prefix":"10.3390","volume":"19","author":[{"given":"Nguyen Minh","family":"Hieu","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2662-7077","authenticated-orcid":false,"given":"Cao Van","family":"Phuoc","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Truong Thi","family":"Hien","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nguyen Duc","family":"Chinh","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nguyen Duc","family":"Quang","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunjoong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0295-4030","authenticated-orcid":false,"given":"Jong-Ryul","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0964-8527","authenticated-orcid":false,"given":"Dojin","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1080\/10408430490888977","article-title":"Oxide materials for development of integrated gas sensors\u2014A comprehensive review","volume":"29","author":"Eranna","year":"2004","journal-title":"Crit. 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