{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T01:42:27Z","timestamp":1785202947042,"version":"3.55.0"},"reference-count":24,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2013,3,20]],"date-time":"2013-03-20T00:00:00Z","timestamp":1363737600000},"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>Two-dimensional (2D) ZnO nanowalls were prepared on a glass substrate by a low-temperature thermal evaporation method, in which the fabrication process did not use a metal catalyst or the pre-deposition of a ZnO seed layer on the substrate. The nanowalls were characterized for their surface morphology, and the structural and optical properties were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL). The fabricated ZnO nanowalls have many advantages, such as low growth temperature and good crystal quality, while being fast, low cost, and easy to fabricate. Methane sensor measurements of the ZnO nanowalls show a high sensitivity to methane gas, and rapid response and recovery times. These unique characteristics are attributed to the high surface-to-volume ratio of the ZnO nanowalls. Thus, the ZnO nanowall methane sensor is a potential gas sensor candidate owing to its good performance.<\/jats:p>","DOI":"10.3390\/s130303941","type":"journal-article","created":{"date-parts":[[2013,3,20]],"date-time":"2013-03-20T13:23:35Z","timestamp":1363785815000},"page":"3941-3950","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":66,"title":["Simple Fabrication Process for 2D ZnO Nanowalls and  Their Potential Application as a Methane Sensor"],"prefix":"10.3390","volume":"13","author":[{"given":"Tse-Pu","family":"Chen","sequence":"first","affiliation":[{"name":"Institute of Microelectronics and Department of Electrical Engineering,  Center for Micro\/Nano Science and Technology Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4126-0576","authenticated-orcid":false,"given":"Sheng-Po","family":"Chang","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics and Department of Electrical Engineering,  Center for Micro\/Nano Science and Technology Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5432-0980","authenticated-orcid":false,"given":"Fei-Yi","family":"Hung","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Institute of Nanotechnology and Microsystems Engineering, Center for Micro\/Nano Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shoou-Jinn","family":"Chang","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics and Department of Electrical Engineering,  Center for Micro\/Nano Science and Technology Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhan-Shuo","family":"Hu","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics and Department of Electrical Engineering,  Center for Micro\/Nano Science and Technology Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kuan-Jen","family":"Chen","sequence":"additional","affiliation":[{"name":"The Instrument Center, National Cheng Kung University, Tainan 701, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5872","DOI":"10.1002\/adma.201202749","article-title":"Stacking-order-dependent optoelectronic properties of bilayer nanofilm photodetectors made from hollow ZnS and ZnO microspheres","volume":"24","author":"Hu","year":"2012","journal-title":"Adv. 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