{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T17:58:20Z","timestamp":1784656700561,"version":"3.55.0"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2013,5,10]],"date-time":"2013-05-10T00:00:00Z","timestamp":1368144000000},"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>Hierarchical flower-like ZnO nanorods, net-like ZnO nanofibers and ZnO nanobulks have been successfully synthesized via a surfactant assisted hydrothemal method. The synthesized products were characterized by X-ray powder diffraction and field emission scanning electron microscopy, respectively. A possible growth mechanism of the various hierarchical ZnO nanostructures is discussed in detail. Gas sensors based on the as-prepared ZnO nanostructures were fabricated by screen-printing on a flat ceramic substrate. Furthermore, their gas sensing characteristics towards methane were systematically investigated. Methane is an important characteristic hydrocarbon contaminant found dissolved in power transformer oil as a result of faults. We find that the hierarchical flower-like ZnO nanorods and net-like ZnO nanofibers samples show higher gas response and lower operating temperature with rapid response-recovery time compared to those of sensors based on ZnO nanobulks. These results present a feasible way of exploring high performance sensing materials for on-site detection of characteristic fault gases dissolved in transformer oil.<\/jats:p>","DOI":"10.3390\/s130506171","type":"journal-article","created":{"date-parts":[[2013,5,10]],"date-time":"2013-05-10T14:17:28Z","timestamp":1368195448000},"page":"6171-6182","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":85,"title":["Hydrothermal Synthesis of Various Hierarchical ZnO Nanostructures and Their Methane Sensing Properties"],"prefix":"10.3390","volume":"13","author":[{"given":"Qu","family":"Zhou","sequence":"first","affiliation":[{"name":"State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400030, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weigen","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400030, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lingna","family":"Xu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400030, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shudi","family":"Peng","sequence":"additional","affiliation":[{"name":"Chongqing Electric Power Research Institute, Chongqing 401123, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,5,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4132","DOI":"10.1109\/TIE.2009.2021174","article-title":"Global loss evaluation methods for nonsinusoidally fed medium-frequency power transformers","volume":"56","author":"Villar","year":"2009","journal-title":"IEEE Trans. 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