{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T13:40:36Z","timestamp":1791639636702,"version":"4.3.4"},"reference-count":34,"publisher":"American Chemical Society (ACS)","issue":"12","license":[{"start":{"date-parts":[[2018,12,28]],"date-time":"2018-12-28T00:00:00Z","timestamp":1545955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/pubs.acs.org\/page\/policy\/authorchoice_termsofuse.html"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,12,31]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The use of metal-oxide sensors for effectively detecting hydrogen sulfide (H2S) gas at room temperature is currently hindered by their inadequate sensitivity and selectivity. Using a lucid fabrication strategy, we report a room-temperature, highly sensitive, and selective H2S gas sensor using NiO-modified WO3 nanorod (one-dimensional\u2013one-dimensional) random networks. The observed improvements in gas-sensing sensitivity stem from the synergistic effects of various contributions inside the sensing heterostructure, such as bulk nanorod, p\u2013n heterojunction at the interface of these two dissimilar oxides, and gas-induced conducting species due to sulfurization (WS2\u2013x and NiS1\u2013x). An in situ impedance measurement during gas exposure was used to investigate the influence of these effects. The analysis revealed that these contributing factors can be either cooperating or competing and lead to either increased or decreased sensitivity, respectively. The presence of semimetallic species (NiS, WS2) was further confirmed by in situ X-ray diffraction analysis of the heterostructure nanorod sample with H2S gas exposure. The related sensing mechanism in the heterostructures is presented with a conduction pathway model. The room-temperature-operated nanorod heterostructure sensors showed a lower detection limit of H2S at \u223c0.5 ppm, which is significantly lower than its toxicity limiting value \u223c10 ppm, per the Environmental Protection Agency. The nanorod heterostructure sensors can be used for real-time, low-cost, room-temperature alarms in an H2S monitoring system.<\/jats:p>","DOI":"10.1021\/acsomega.8b01981","type":"journal-article","created":{"date-parts":[[2018,12,28]],"date-time":"2018-12-28T09:13:21Z","timestamp":1545988401000},"page":"18685-18693","source":"Crossref","is-referenced-by-count":28,"title":["In Operando Impedance Spectroscopic Analysis on NiO\u2013WO3 Nanorod Heterojunction Random Networks for Room-Temperature\nH2S Detection"],"prefix":"10.1021","volume":"3","author":[{"given":"Yale","family":"Wang","sequence":"first","affiliation":[{"name":"University of Wisconsin\u2212Milwaukee , , 3200 North Cramer Street , , ,","place":["Milwaukee, Wisconsin, United States, 53211"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arnab","family":"Maity","sequence":"additional","affiliation":[{"name":"University of Wisconsin\u2212Milwaukee , , 3200 North Cramer Street , , ,","place":["Milwaukee, Wisconsin, United States, 53211"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyu","family":"Sui","sequence":"additional","affiliation":[{"name":"University of Wisconsin\u2212Milwaukee , , 3200 North Cramer Street , , ,","place":["Milwaukee, Wisconsin, United States, 53211"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haihui","family":"Pu","sequence":"additional","affiliation":[{"name":"University of Wisconsin\u2212Milwaukee , , 3200 North Cramer Street , , ,","place":["Milwaukee, Wisconsin, United States, 53211"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3319-4203","authenticated-orcid":true,"given":"Shun","family":"Mao","sequence":"additional","affiliation":[{"name":"Tongji University , , 1239 Siping Road , ,","place":["Shanghai, China, 200092"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niraj K.","family":"Singh","sequence":"additional","affiliation":[{"name":"Sigma-Aldrich Corp. , , 6000 North Teutonia Avenue , , ,","place":["Milwaukee, Wisconsin, United States, 53209"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2615-1347","authenticated-orcid":true,"given":"Junhong","family":"Chen","sequence":"additional","affiliation":[{"name":"University of Wisconsin\u2212Milwaukee , , 3200 North Cramer Street , , ,","place":["Milwaukee, Wisconsin, United States, 53211"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2018,12,28]]},"reference":[{"key":"2026090207580072400_cit1","unstructured":"https:\/\/www.osha.gov\/SLTC\/hydrogensulfide\/hazards.htl."},{"key":"2026090207580072400_cit2","doi-asserted-by":"publisher","first-page":"25","DOI":"10.3109\/10408448409029321","article-title":"A Critical Review of\nthe Literature on Hydrogen Sulfide Toxicity","author":"Beauchamp","year":"2008","journal-title":"CRC Crit. 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