{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T19:48:11Z","timestamp":1791143291858,"version":"4.1.0"},"reference-count":62,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2014,8,11]],"date-time":"2014-08-11T00:00:00Z","timestamp":1407715200000},"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>An inexpensive single-step carbon-assisted thermal evaporation method for the growth of SnO2-core\/ZnO-shell nanostructures is described, and the ethanol sensing properties are presented. The structure and phases of the grown nanostructures are investigated by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. XRD analysis indicates that the core-shell nanostructures have good crystallinity. At a lower growth duration of 15 min, only SnO2 nanowires with a rectangular cross-section are observed, while the ZnO shell is observed when the growth time is increased to 30 min. Core-shell hierarchical nanostructures are present for a growth time exceeding 60 min. The growth mechanism for SnO2-core\/ZnO-shell nanowires and hierarchical nanostructures are also discussed. The sensitivity of the synthesized SnO2-core\/ZnO-shell nanostructures towards ethanol sensing is investigated. Results show that the SnO2-core\/ZnO-shell nanostructures deposited at 90 min exhibit enhanced sensitivity to ethanol. The sensitivity of  SnO2-core\/ZnO-shell nanostructures towards 20 ppm ethanol gas at 400 \u00b0C is about  ~5-times that of SnO2 nanowires. This improvement in ethanol gas response is attributed to high active sensing sites and the synergistic effect of the encapsulation of SnO2 by  ZnO nanostructures.<\/jats:p>","DOI":"10.3390\/s140814586","type":"journal-article","created":{"date-parts":[[2014,8,11]],"date-time":"2014-08-11T10:14:24Z","timestamp":1407752064000},"page":"14586-14600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":87,"title":["Enhanced Ethanol Gas Sensing Properties of  SnO2-Core\/ZnO-Shell Nanostructures"],"prefix":"10.3390","volume":"14","author":[{"given":"T.","family":"Tharsika","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Malaya,  Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A.","family":"Haseeb","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Malaya,  Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheikh","family":"Akbar","sequence":"additional","affiliation":[{"name":"Center for Industrial Sensors and Measurements (CISM), Department of Materials Science and Engineering, Ohio State University, 2041 College Road, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohd","family":"Sabri","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Malaya,  Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3254-9420","authenticated-orcid":false,"given":"Wong","family":"Hoong","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Malaya,  Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/0925-4005(94)01278-P","article-title":"Recent developments in semiconducting thin-film gas sensors","volume":"23","author":"Sberveglieri","year":"1995","journal-title":"Sens. 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