{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T22:07:03Z","timestamp":1768342023842,"version":"3.49.0"},"reference-count":26,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2009,9,16]],"date-time":"2009-09-16T00:00:00Z","timestamp":1253059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new type of capacitive humidity sensor is introduced in this paper. The sensor consists of two plate electrodes coated with MWCNT films and four pieces of isolating medium at the four corners of the sensor. According to capillary condensation, the capacitance signal of the sensor is sensitive to relative humidity (RH), which could be transformed to voltage signal by a capacitance to voltage converter circuit. The sensor is tested using different saturated saline solutions at the ambient temperature of 25 \u00b0C, which yielded approximately 11% to 97% RH, respectively. The function of the MWCNT films, the effect of electrode distance, the temperature character and the repeatability of the sensor are discussed in this paper.<\/jats:p>","DOI":"10.3390\/s90907431","type":"journal-article","created":{"date-parts":[[2009,9,16]],"date-time":"2009-09-16T12:07:21Z","timestamp":1253102841000},"page":"7431-7444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":133,"title":["A Capacitive Humidity Sensor Based on Multi-Wall Carbon Nanotubes (MWCNTs)"],"prefix":"10.3390","volume":"9","author":[{"given":"Wei-Ping","family":"Chen","sequence":"first","affiliation":[{"name":"Department of Microelectronics, Harbin Institute of Technology, Harbin, Heilongjiang, China"},{"name":"Key Laboratory of Micro-Systems and Micro-Structures Manufacturing, Ministry of Education, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhen-Gang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Microelectronics, Harbin Institute of Technology, Harbin, Heilongjiang, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiao-Wei","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Microelectronics, Harbin Institute of Technology, Harbin, Heilongjiang, China"},{"name":"Key Laboratory of Micro-Systems and Micro-Structures Manufacturing, Ministry of Education, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhong-Xin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Microelectronics, Harbin Institute of Technology, Harbin, Heilongjiang, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chun-Guang","family":"Suo","sequence":"additional","affiliation":[{"name":"Department of Microelectronics, Harbin Institute of Technology, Harbin, Heilongjiang, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2009,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1016\/j.snb.2005.02.040","article-title":"Electrical and humidity sensing properties of carbon nanotubes-SiO2-poly (2-acrylamido- 2-methylpropane sulfonate)","volume":"113","author":"Su","year":"2006","journal-title":"Sens. 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