{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T19:53:03Z","timestamp":1774036383807,"version":"3.50.1"},"reference-count":53,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,5]],"date-time":"2018-10-05T00:00:00Z","timestamp":1538697600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007053","name":"Korea Institute of Energy Technology Evaluation and Planning","doi-asserted-by":"publisher","award":["20158520000210"],"award-info":[{"award-number":["20158520000210"]}],"id":[{"id":"10.13039\/501100007053","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005073","name":"Agency for Defense Development","doi-asserted-by":"publisher","award":["UD160050BD"],"award-info":[{"award-number":["UD160050BD"]}],"id":[{"id":"10.13039\/501100005073","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Few studies have investigated the gas-sensing properties of graphene oxide\/titanium dioxide (GO\/TiO2) composite combined with photocatalytic effect. Room temperature gas-sensing properties of the GO\/TiO2 composite were investigated towards various reducing gases. The composite sensor showed an enhanced gas response and a faster recovery time than a pure GO sensor due to the synergistic effect of the hybridization, such as creation of a hetero-junction at the interface and modulation of charge carrier density. However, the issue of long-term stability at room temperature still remains unsolved even after construction of a composite structure. To address this issue, the surface and hetero-junction of the GO\/TiO2 composite were engineered via a UV process. A photocatalytic effect of TiO2 induced the reduction of the GO phase in the composite solution. The comparison of gas-sensing properties before and after the UV process clearly showed the transition from n-type to p-type gas-sensing behavior toward reducing gases. This transition revealed that the dominant sensing material is GO, and TiO2 enhanced the gas reaction by providing more reactive sites. With a UV-treated composite sensor, the function of identifying target gas was maintained over a one-month period, showing strong resistance to humidity.<\/jats:p>","DOI":"10.3390\/s18103334","type":"journal-article","created":{"date-parts":[[2018,10,5]],"date-time":"2018-10-05T12:16:44Z","timestamp":1538741804000},"page":"3334","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Enhanced Gas-Sensing Performance of GO\/TiO2 Composite by Photocatalysis"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5046-3060","authenticated-orcid":false,"given":"Eunji","family":"Lee","sequence":"first","affiliation":[{"name":"Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9742-6953","authenticated-orcid":false,"given":"Doohee","family":"Lee","sequence":"additional","affiliation":[{"name":"Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jaesik","family":"Yoon","sequence":"additional","affiliation":[{"name":"Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yilin","family":"Yin","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"You Na","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biological Engineering, Gachon University, Seongnam 13120, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6208-3639","authenticated-orcid":false,"given":"Sunil","family":"Uprety","sequence":"additional","affiliation":[{"name":"Department of Physics, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Young Soo","family":"Yoon","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biological Engineering, Gachon University, Seongnam 13120, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5013-4005","authenticated-orcid":false,"given":"Dong-Joo","family":"Kim","sequence":"additional","affiliation":[{"name":"Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1007\/s11947-008-0154-y","article-title":"Carbon dioxide (CO2) sensors for the agri-food industry\u2014A review","volume":"2","author":"Neethirajan","year":"2009","journal-title":"Food Bioprocess Tech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5469","DOI":"10.3390\/s100605469","article-title":"Metal oxide semi-conductor gas sensors in environmental monitoring","volume":"10","author":"Fine","year":"2010","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3693","DOI":"10.1002\/adfm.201202601","article-title":"Ultrathin graphene nanofiltration membrane for water purification","volume":"23","author":"Han","year":"2013","journal-title":"Adv. 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