{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T17:52:05Z","timestamp":1770832325370,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2020,8,22]],"date-time":"2020-08-22T00:00:00Z","timestamp":1598054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61901186"],"award-info":[{"award-number":["61901186"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Special Innovation Projects of Universities in Guangdong province","award":["2019KTSCX178"],"award-info":[{"award-number":["2019KTSCX178"]}]},{"name":"Program for Innovative Research Team of Huizhou University","award":["IRTHZU"],"award-info":[{"award-number":["IRTHZU"]}]},{"name":"Open Project Program of Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices","award":["No. EFMD2020002Z"],"award-info":[{"award-number":["No. EFMD2020002Z"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Hierarchical three-dimensional (3D) flower-like n-ZnO\/p-NiO heterostructures with various ZnxNiy molar ratios (Zn5Ni1, Zn2Ni1, Zn1Ni1, Zn1Ni2 and Zn1Ni5) were synthesized by a facile hydrothermal method. Their crystal phase, surface morphology, elemental composition and chemical state were comprehensively investigated by XRD, SEM, EDS, TEM and XPS techniques. Gas sensing measurements were conducted on all the as-developed ZnxNiy-based sensors toward ammonia (NH3) detection under various working temperatures from 160 to 340 \u00b0C. In particular, the as-prepared Zn1Ni2 sensor exhibited superior NH3 sensing performance under optimum working temperature (280 \u00b0C) including high response (25 toward 100 ppm), fast response\/recovery time (16 s\/7 s), low detection limit (50 ppb), good selectivity and long-term stability. The enhanced NH3 sensing capabilities of Zn1Ni2 sensor could be attributed to both the specific hierarchical structure which facilitates the adsorption of NH3 molecules and produces much more contact sites, and the improved gas response characteristics of p-n heterojunctions. The obtained results clear demonstrated that the optimum n-ZnO\/p-NiO heterostructure is indeed very promising sensing material toward NH3 detection for different applications.<\/jats:p>","DOI":"10.3390\/s20174754","type":"journal-article","created":{"date-parts":[[2020,8,23]],"date-time":"2020-08-23T21:28:06Z","timestamp":1598218086000},"page":"4754","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["NH3 Sensor Based on 3D Hierarchical Flower-Shaped n-ZnO\/p-NiO Heterostructures Yields Outstanding Sensing Capabilities at ppb Level"],"prefix":"10.3390","volume":"20","author":[{"given":"Zhenting","family":"Zhao","sequence":"first","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices, Huizhou University, Huizhou 516001, Guangdong, China"},{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"given":"Haoyue","family":"Yang","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"given":"Zihan","family":"Wei","sequence":"additional","affiliation":[{"name":"Department of Solid State Science, Faculty of Science, Ghent University Global Campus, 119 Songdomunhwa-ro, Yeonsu-gu, Incheon 21985, Korea"}]},{"given":"Yan","family":"Xue","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"given":"Yongjiao","family":"Sun","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"given":"Wenlei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"given":"Pengwei","family":"Li","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3761-2671","authenticated-orcid":false,"given":"Weiping","family":"Gong","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices, Huizhou University, Huizhou 516001, Guangdong, China"}]},{"given":"Serge","family":"Zhuiykov","sequence":"additional","affiliation":[{"name":"Department of Solid State Science, Faculty of Science, Ghent University Global Campus, 119 Songdomunhwa-ro, Yeonsu-gu, Incheon 21985, Korea"}]},{"given":"Jie","family":"Hu","sequence":"additional","affiliation":[{"name":"Center of Nano Energy and Devices, College of Information and computer, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21974","DOI":"10.1021\/acsami.0c04810","article-title":"Design and synthesis of air-stable p-channel-conjugated polymers for high signal-to-drift nitrogen dioxide and ammonia sensing","volume":"12","author":"Mukhopadhyaya","year":"2020","journal-title":"ACS Appl. 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