{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T05:54:14Z","timestamp":1784872454259,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,16]],"date-time":"2024-08-16T00:00:00Z","timestamp":1723766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Liaoning Provincial Department of Education Basic Research Project","award":["JYTMS20231087"],"award-info":[{"award-number":["JYTMS20231087"]}]},{"name":"Liaoning Provincial Department of Education Basic Research Project","award":["2022-BS-102"],"award-info":[{"award-number":["2022-BS-102"]}]},{"name":"Liaoning Provincial Department of Education Basic Research Project","award":["140238"],"award-info":[{"award-number":["140238"]}]},{"DOI":"10.13039\/501100005047","name":"Natural Science Foundation of Liaoning Province","doi-asserted-by":"publisher","award":["JYTMS20231087"],"award-info":[{"award-number":["JYTMS20231087"]}],"id":[{"id":"10.13039\/501100005047","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005047","name":"Natural Science Foundation of Liaoning Province","doi-asserted-by":"publisher","award":["2022-BS-102"],"award-info":[{"award-number":["2022-BS-102"]}],"id":[{"id":"10.13039\/501100005047","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005047","name":"Natural Science Foundation of Liaoning Province","doi-asserted-by":"publisher","award":["140238"],"award-info":[{"award-number":["140238"]}],"id":[{"id":"10.13039\/501100005047","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Fundamental Research Funds for the Central Universities","award":["JYTMS20231087"],"award-info":[{"award-number":["JYTMS20231087"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["2022-BS-102"],"award-info":[{"award-number":["2022-BS-102"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["140238"],"award-info":[{"award-number":["140238"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, alkali metal Rb-loaded ZnO\/In2O3 heterojunctions were synthesized using a combination of hydrothermal and impregnation methods. The morphology and structure of the synthesized samples were characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. The enhancement mechanism of the nitrogen dioxide gas sensing performance of the Rb-loaded ZnO\/In2O3 heterojunctions was systematically investigated at room temperature using density-functional theory calculations and experimental validation. The experimental tests showed that the Rb-loaded ZnO\/In2O3 sensor achieved an excellent response value of 24.2 for 1 ppm NO2, with response and recovery times of 55 and 21 s, respectively. This result is 20 times higher than that of pure ZnO sensors and two times higher than that of ZnO\/In2O3 sensors, indicating that the Rb-loaded ZnO\/In2O3 sensor has a more pronounced enhancement in performance for NO2. This study not only revealed the mechanism by which Rb loading affects the electronic structure and gas molecule adsorption behavior on the surface of ZnO\/In2O3 heterojunctions but also provides theoretical guidance and technical support for the development of high-performance room-temperature NO2 sensors.<\/jats:p>","DOI":"10.3390\/s24165311","type":"journal-article","created":{"date-parts":[[2024,8,16]],"date-time":"2024-08-16T06:23:20Z","timestamp":1723789400000},"page":"5311","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Enhanced NO2 Gas Sensing Properties Based on Rb-Doped ZnO\/In2O3 Heterojunctions at Room Temperature: A Combined DFT and Experimental Study"],"prefix":"10.3390","volume":"24","author":[{"given":"Yaning","family":"Yang","sequence":"first","affiliation":[{"name":"College of Information &Communication Engineering, Dalian Minzu University, Dalian 116600, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiawen","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Information &Communication Engineering, Dalian Minzu University, Dalian 116600, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhihua","family":"Luo","sequence":"additional","affiliation":[{"name":"College of Information &Communication Engineering, Dalian Minzu University, Dalian 116600, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhixin","family":"Luo","sequence":"additional","affiliation":[{"name":"College of Information &Communication Engineering, Dalian Minzu University, Dalian 116600, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5654-403X","authenticated-orcid":false,"given":"Yanhui","family":"Sun","sequence":"additional","affiliation":[{"name":"College of Information &Communication Engineering, Dalian Minzu University, Dalian 116600, China"},{"name":"School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1016\/j.snb.2004.10.030","article-title":"Sensing characteristics of tin-doped ZnO thin films as NO2 gas sensor","volume":"107","author":"Shishiyanu","year":"2005","journal-title":"Sens. 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