{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T12:26:26Z","timestamp":1780921586651,"version":"3.54.1"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,20]],"date-time":"2018-03-20T00:00:00Z","timestamp":1521504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Flexible sensors connected to cell phones are a promising technology that can aid in continuously monitoring signals in our daily lives, such as an individual\u2019s health status and information from buildings, farms, and industry. Among such signals, real-time humidity monitoring is crucial to a comfortable life, as human bodies, plants, and industrial environments require appropriate humidity to be maintained. We propose a hydrophilic polytetrafluoroethylene (H-PTFE)-based flexible humidity sensor integrated with readout circuitry, wireless communication, and a mobile battery. To enhance its sensitivity, linearity, and reliability, treatment with sodium hydroxide implements additional hydroxyl (OH) groups, which further enhance the sensitivity, create a strong linearity with respect to variations in relative humidity, and produce a relatively free hysteresis. Furthermore, to create robust mechanical stability, cyclic upward bending was performed for up to 3000 cycles. The overall electrical and mechanical results demonstrate that the flexible real-time H-PTFE humidity sensor system is suitable for applications such as wearable smart devices.<\/jats:p>","DOI":"10.3390\/s18030921","type":"journal-article","created":{"date-parts":[[2018,3,20]],"date-time":"2018-03-20T06:57:11Z","timestamp":1521529031000},"page":"921","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Enhanced Moisture-Reactive Hydrophilic-PTFE-Based Flexible Humidity Sensor for Real-Time Monitoring"],"prefix":"10.3390","volume":"18","author":[{"given":"Heekyeong","family":"Park","sequence":"first","affiliation":[{"name":"School of Advanced Materials Science &amp; Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sungho","family":"Lee","sequence":"additional","affiliation":[{"name":"Korea Electronics Technology Institute, Gyeonggi 13488, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seok","family":"Jeong","sequence":"additional","affiliation":[{"name":"School of Advanced Materials Science &amp; Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ui","family":"Jung","sequence":"additional","affiliation":[{"name":"School of Advanced Materials Science &amp; Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kidong","family":"Park","sequence":"additional","affiliation":[{"name":"Division of Electrical and Computer Engineering, Electrical Engineering Building, Louisiana State University, Baton Rouge, LA 70809, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Lee","sequence":"additional","affiliation":[{"name":"Korea Electronics Technology Institute, Gyeonggi 13488, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1747-4539","authenticated-orcid":false,"given":"Sunkook","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Advanced Materials Science &amp; Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1974-9789","authenticated-orcid":false,"given":"Joonhyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Device &amp; System Research Center, Samsung Advanced Institute of Technology, Suwon 443-803, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1016\/j.snb.2016.06.041","article-title":"Optimization of porous anodic alumina nanostructure for ultra high sensitive humidity sensor","volume":"237","author":"Sharma","year":"2016","journal-title":"Sens. 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