{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T15:47:43Z","timestamp":1775490463639,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,11,27]],"date-time":"2019-11-27T00:00:00Z","timestamp":1574812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, ICT","award":["NRF-2019M3F2A1073385"],"award-info":[{"award-number":["NRF-2019M3F2A1073385"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper introduces a strategy for improving the sensitivity of a gas sensor to NO2 gas. The gas sensor was fabricated using urchin-like ZnO nanostructures grown on MgO particles via vapor-phase growth and decorated with MgZnO nanoparticles via a sol-gel process. The urchin-like ZnO gas sensor decorated with MgZnO showed higher sensitivity to NO2 gas than a pristine urchin-like ZnO gas sensor. When ZnO and MgZnO form a heterojunction, a two-dimensional electron gas is generated. This improves the performance of the fabricated gas sensor. The growth morphology, atomic composition, and phase structure were confirmed through field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction, respectively.<\/jats:p>","DOI":"10.3390\/s19235195","type":"journal-article","created":{"date-parts":[[2019,11,27]],"date-time":"2019-11-27T11:07:00Z","timestamp":1574852820000},"page":"5195","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Sensitivity Improvement of Urchin-Like ZnO Nanostructures Using Two-Dimensional Electron Gas in MgZnO\/ZnO"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-3863-0265","authenticated-orcid":false,"given":"So-Young","family":"Bak","sequence":"first","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeongseok","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoojong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Se-Hyeong","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyoungwan","family":"Woo","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sanghyun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Smart Hybrid Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Moonsuk","family":"Yi","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.snb.2014.07.074","article-title":"Nanoscale metal oxide-based heterojunctions for gas sensing: A review","volume":"204","author":"Miller","year":"2014","journal-title":"Sens. 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