{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T09:16:33Z","timestamp":1784970993886,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,4]],"date-time":"2021-06-04T00:00:00Z","timestamp":1622764800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2019R1A2C2005933"],"award-info":[{"award-number":["2019R1A2C2005933"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003661","name":"Korea Institute for Advancement of Technology","doi-asserted-by":"publisher","award":["P0002397"],"award-info":[{"award-number":["P0002397"]}],"id":[{"id":"10.13039\/501100003661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Flexible and wearable pressure sensors have attracted significant attention owing to their roles in healthcare monitoring and human\u2013machine interfaces. In this study, we introduce a wide-range, highly sensitive, stable, reversible, and biocompatible pressure sensor based on a porous Ecoflex with tilted air-gap-structured and carbonized cotton fabric (CCF) electrodes. The knitted structure of electrodes demonstrated the effectiveness of the proposed sensor in enhancing the pressure-sensing performance in comparison to a woven structure due to the inherent properties of naturally generated space. In addition, the presence of tilted air gaps in the porous elastomer provided high deformability, thereby significantly improving the sensor sensitivity compared to other dielectric structures that have no or vertical air gaps. The combination of knitted CCF electrodes and the porous dielectric with tilted air gaps achieved a sensitivity of 24.5 \u00d7 10\u22123 kPa\u22121 at 100 kPa, along with a wide detection range (1 MPa). It is also noteworthy that this novel method is low-cost, facile, scalable, and ecofriendly. Finally, the proposed sensor integrated into a smart glove detected human motions of grasping water cups, thus demonstrating its potential applications in wearable electronics.<\/jats:p>","DOI":"10.3390\/s21113895","type":"journal-article","created":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T01:56:40Z","timestamp":1623031000000},"page":"3895","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Carbonized Cotton Fabric-Based Flexible Capacitive Pressure Sensor Using a Porous Dielectric Layer with Tilted Air Gaps"],"prefix":"10.3390","volume":"21","author":[{"given":"Yelin","family":"Ko","sequence":"first","affiliation":[{"name":"Department of Organic Materials and Fiber Engineering, Soongsil University, Seoul 06978, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chi Cuong","family":"Vu","sequence":"additional","affiliation":[{"name":"Department of Organic Materials and Fiber Engineering, Soongsil University, Seoul 06978, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1969-5730","authenticated-orcid":false,"given":"Jooyong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Organic Materials and Fiber Engineering, Soongsil University, Seoul 06978, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108607","DOI":"10.1016\/j.compositesb.2021.108607","article-title":"Fabrication of hierarchically porous structured PDMS composites and their application as a flexible capacitive pressure sensor","volume":"211","author":"Hwang","year":"2021","journal-title":"Compos. B Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"12665","DOI":"10.1039\/D0TA02221G","article-title":"Graphene decorated carbonized cellulose fabric for physiological signal monitoring and energy harvesting","volume":"8","author":"Wu","year":"2020","journal-title":"J. Mater. Chem. A"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Jung, Y., Lee, W., Jung, K., Park, B., Park, J., Ko, J., and Cho, H. (2020). A highly sensitive and flexible capacitive pressure sensor based on a porous three-dimensional PDMS\/microsphere composite. Polymers, 12.","DOI":"10.3390\/polym12061412"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4485","DOI":"10.1002\/adma.201504249","article-title":"Wearable keyboard using conducting polymer electrodes on textiles","volume":"28","author":"Takamatsu","year":"2016","journal-title":"Adv. Mater."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1803018","DOI":"10.1002\/smll.201803018","article-title":"A flexible wearable pressure sensor with bioinspired microcrack and interlocking for full-range human\u2013machine interfacing","volume":"14","author":"Guo","year":"2018","journal-title":"Small"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Fastier-Wooller, J., Dinh, T., Dau, V.T., Phan, H.-P., Yang, F., and Dao, D.V. (2018). Low-cost graphite on paper pressure sensor for a robot gripper with a trivial fabrication process. Sensors, 18.","DOI":"10.3390\/s18103300"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2000179","DOI":"10.1002\/aisy.202000179","article-title":"Microporous Induced Fully Printed Pressure Sensor for Wearable Soft Robotics Machine Interfaces","volume":"2","author":"Sekine","year":"2020","journal-title":"Adv. Intell. Syst."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Zhu, L., Wang, Y., Mei, D., and Jiang, C.J.M. (2020). Development of Fully Flexible Tactile Pressure Sensor with Bilayer Interlaced Bumps for Robotic Grasping Applications. Micromachines, 11.","DOI":"10.3390\/mi11080770"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1704149","DOI":"10.1002\/smll.201704149","article-title":"Piezoresistive pressure sensor based on synergistical innerconnect polyvinyl alcohol nanowires\/wrinkled graphene film","volume":"14","author":"Liu","year":"2018","journal-title":"Small"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"29466","DOI":"10.1021\/acsami.9b09265","article-title":"Highly sensitive flexible piezoresistive pressure sensor developed using biomimetically textured porous materials","volume":"11","author":"Zhao","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1700237","DOI":"10.1002\/admt.201700237","article-title":"A highly sensitive capacitive-based soft pressure sensor based on a conductive fabric and a microporous dielectric layer","volume":"3","author":"Atalay","year":"2018","journal-title":"Adv. Mater. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"20978","DOI":"10.1007\/s10854-018-0242-3","article-title":"Ultra-highly sensitive, low hysteretic and flexible pressure sensor based on porous MWCNTs\/Ecoflex elastomer composites","volume":"29","author":"Wen","year":"2018","journal-title":"J. Mater. Sci. Mater. Electron."},{"key":"ref_13","first-page":"6558","article-title":"A flexible capacitive pressure sensor for wearable respiration monitoring system","volume":"17","author":"Park","year":"2017","journal-title":"IEEE Sens. J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.mee.2017.04.028","article-title":"A novel means of fabricating microporous structures for the dielectric layers of capacitive pressure sensor","volume":"179","author":"Yoon","year":"2017","journal-title":"Microelectron. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"111789","DOI":"10.1016\/j.sna.2019.111789","article-title":"Flexible piezoelectric pressure sensor based on polydopamine-modified BaTiO3\/PVDF composite film for human motion monitoring","volume":"301","author":"Yang","year":"2020","journal-title":"Sens. Actuator A Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"9008","DOI":"10.1021\/acsami.9b21052","article-title":"Glycine\u2013chitosan-based flexible biodegradable piezoelectric pressure sensor","volume":"12","author":"Hosseini","year":"2020","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2896","DOI":"10.1002\/adma.201503407","article-title":"Self-powered high-resolution and pressure-sensitive triboelectric sensor matrix for real-time tactile mapping","volume":"28","author":"Wang","year":"2016","journal-title":"Adv. Mater."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"14997","DOI":"10.1021\/acsami.9b02049","article-title":"Flexible, tunable, and ultrasensitive capacitive pressure sensor with microconformal graphene electrodes","volume":"11","author":"Yang","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"13232","DOI":"10.1039\/C8TC04297G","article-title":"A highly sensitive and flexible capacitive pressure sensor based on a micro-arrayed polydimethylsiloxane dielectric layer","volume":"6","author":"Ma","year":"2018","journal-title":"J. Mater. Chem. C"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1039\/C4MH00147H","article-title":"Advances of flexible pressure sensors toward artificial intelligence and health care applications","volume":"2","author":"Zang","year":"2015","journal-title":"Mater. Horiz."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"104436","DOI":"10.1016\/j.nanoen.2019.104436","article-title":"A flexible, ultra-highly sensitive and stable capacitive pressure sensor with convex microarrays for motion and health monitoring","volume":"70","author":"Xiong","year":"2020","journal-title":"Nano Energy"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1903100","DOI":"10.1002\/adfm.201903100","article-title":"Rational design of capacitive pressure sensors based on pyramidal microstructures for specialized monitoring of biosignals","volume":"30","author":"Ruth","year":"2020","journal-title":"Adv. Funct. Mater."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"17796","DOI":"10.1021\/acsami.9b03718","article-title":"Flexible capacitive pressure sensor enhanced by tilted micropillar arrays","volume":"11","author":"Luo","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"26314","DOI":"10.1021\/acsami.7b05753","article-title":"Highly sensitive flexible pressure sensor based on silver nanowires-embedded polydimethylsiloxane electrode with microarray structure","volume":"9","author":"Shuai","year":"2017","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1698","DOI":"10.1021\/acsami.9b20097","article-title":"Synergetic effect of porous elastomer and percolation of carbon nanotube filler toward high performance capacitive pressure sensors","volume":"12","author":"Choi","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"16922","DOI":"10.1021\/acsami.6b04225","article-title":"Highly sensitive, flexible, and wearable pressure sensor based on a giant piezocapacitive effect of three-dimensional microporous elastomeric dielectric layer","volume":"8","author":"Kwon","year":"2016","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.flatc.2018.07.001","article-title":"A porous graphene\/polydimethylsiloxane composite by chemical foaming for simultaneous tensile and compressive strain sensing","volume":"10","author":"Long","year":"2018","journal-title":"Flatchem"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"111002","DOI":"10.1016\/j.mee.2019.111002","article-title":"Fabrication of highly sensitive capacitive pressure sensors with porous PDMS dielectric layer via microwave treatment","volume":"215","author":"Kim","year":"2019","journal-title":"Microelectron. Eng."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"859","DOI":"10.1038\/nmat2834","article-title":"Highly sensitive flexible pressure sensors with microstructured rubber dielectric layers","volume":"9","author":"Mannsfeld","year":"2010","journal-title":"Nat. Mater."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"111941","DOI":"10.1016\/j.sna.2020.111941","article-title":"Highly sensitive and flexible wearable pressure sensor with dielectric elastomer and carbon nanotube electrodes","volume":"305","author":"Han","year":"2020","journal-title":"Sens. Actuator A Phys."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"11468","DOI":"10.1039\/D0TC00443J","article-title":"A porous and air gap elastomeric dielectric layer for wearable capacitive pressure sensor with high sensitivity and a wide detection range","volume":"8","author":"Li","year":"2020","journal-title":"J. Mater. Chem. C"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.sna.2019.05.011","article-title":"A high-sensitivity and low-hysteresis flexible pressure sensor based on carbonized cotton fabric","volume":"294","author":"Chang","year":"2019","journal-title":"Sens. Actuator A Phys."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1016\/j.electacta.2018.11.045","article-title":"Carbonized cotton fabric in-situ electrodeposition polypyrrole as high-performance flexible electrode for wearable supercapacitor","volume":"296","author":"Sun","year":"2019","journal-title":"Electrochim. Acta"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1604795","DOI":"10.1002\/adfm.201604795","article-title":"Carbonized cotton fabric for high-performance wearable strain sensors","volume":"27","author":"Zhang","year":"2017","journal-title":"Adv. Funct. Mater."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"3535","DOI":"10.1007\/s10854-016-5954-7","article-title":"Wearable strain sensor made of carbonized cotton cloth","volume":"28","author":"Deng","year":"2017","journal-title":"J. Mater. Sci. Mater. Electron."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"5001","DOI":"10.1007\/s10570-019-02432-x","article-title":"Carbonized cotton fabric-based multilayer piezoresistive pressure sensors","volume":"26","author":"Zhang","year":"2019","journal-title":"Cellulose"},{"key":"ref_37","first-page":"1","article-title":"Effects of carbonization temperature and substrate concentration on the sensing performance of flexible pressure sensor","volume":"126","author":"Chang","year":"2020","journal-title":"J. Appl. Phys."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Eom, S., and Lim, S. (2016). Stretchable complementary split ring resonator (CSRR)-based radio frequency (RF) sensor for strain direction and level detection. Sensors, 16.","DOI":"10.3390\/s16101667"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"20364","DOI":"10.1021\/acsami.6b05177","article-title":"Large area one-step facile processing of microstructured elastomeric dielectric film for high sensitivity and durable sensing over wide pressure range","volume":"8","author":"Chen","year":"2016","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"27562","DOI":"10.1021\/acsami.5b08404","article-title":"Highly stretchable and transparent microfluidic strain sensors for monitoring human body motions","volume":"7","author":"Yoon","year":"2015","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/j.ijsolstr.2017.07.008","article-title":"Effect of pore shape on the effective behavior of viscoelastic porous media","volume":"125","author":"Nguyen","year":"2017","journal-title":"Int. J. Solids Struct."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3895\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:11:04Z","timestamp":1760163064000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3895"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,4]]},"references-count":41,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["s21113895"],"URL":"https:\/\/doi.org\/10.3390\/s21113895","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,4]]}}}