PMID- 31652696 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20200928 IS - 2072-666X (Print) IS - 2072-666X (Electronic) IS - 2072-666X (Linking) VI - 10 IP - 11 DP - 2019 Oct 23 TI - Printed and Flexible Capacitive Pressure Sensor with Carbon Nanotubes based Composite Dielectric Layer. LID - 10.3390/mi10110715 [doi] LID - 715 AB - Flexible pressure sensors have attracted tremendous attention from researchers for their widely applications in tactile artificial intelligence, electric skin, disease diagnosis, and healthcare monitoring. Obtaining flexible pressure sensors with high sensitivity in a low cost and convenient way remains a huge challenge. In this paper, the composite dielectric layer based on the mixture of carbon nanotubes (CNTs) with different aspect ratios and polydimethylsiloxane (PDMS) was employed in flexible capacitive pressure sensor to increase its sensitivity. In addition, the screen printing instead of traditional etching based methods was used to prepare the electrodes array of the sensor. The results showed that the aspect ratio and weight fraction of the CNTs play an important role in improving the sensitivity of the printed capacitive pressure sensor. The prepared capacitive sensor with the CNTs/PDMS composite dielectric layer demonstrated a maximum sensitivity of 2.9 kPa(-1) in the pressure range of 0-450 Pa, by using the CNTs with an aspect ratio of 1250-3750 and the weight fraction of 3.75%. The mechanism study revealed that the increase of the sensitivity of the pressure sensor should be attributed to the relative permittivity increase of the composite dielectric layer under pressure. Meanwhile, the printed 3 x 3 and 10 x 10 sensor arrays showed excellent spatial resolution and uniformity when they were applied to measure the pressure distribution. For further applications, the flexible pressure sensor was integrated on an adhesive bandage to detect the finger bending, as well as used to create Morse code by knocking the sensor to change their capacitance curves. The printed and flexible pressure sensor in this study might be a good candidate for the development of tactile artificial intelligence, intelligent medical diagnosis systems and wearable electronics. FAU - Guo, Zhenxin AU - Guo Z AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. beiyinguozhenxin@163.com. FAU - Mo, Lixin AU - Mo L AUID- ORCID: 0000-0002-6374-239X AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. molixin@bigc.edu.cn. FAU - Ding, Yu AU - Ding Y AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. 15366978028@163.com. FAU - Zhang, Qingqing AU - Zhang Q AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. zqq15201169516@163.com. FAU - Meng, Xiangyou AU - Meng X AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. 17862328880@163.com. FAU - Wu, Zhengtan AU - Wu Z AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. wuzhengtanby@outlook.com. FAU - Chen, Yinjie AU - Chen Y AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. chenyinjie@bigc.edu.cn. FAU - Cao, Meijuan AU - Cao M AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. caomeijuan@bigc.edu.cn. FAU - Wang, Wei AU - Wang W AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. wangwei@bigc.edu.cn. FAU - Li, Luhai AU - Li L AD - Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China. liluhai@bigc.edu.cn. LA - eng GR - KM201810015004/2018 Beijing Municipal Commission of Education project/ GR - CIT&TCD201704051/2017 Beijing Municipal Commission of Education Outstanding young scholars/ GR - 04190118003/002/Beijing Municipal Commission of Education 2011 Collaborative Innovation Centre/ GR - 03150119003/007/2018 Beijing university talents cross training plan (Shipei plan)/ PT - Journal Article DEP - 20191023 PL - Switzerland TA - Micromachines (Basel) JT - Micromachines JID - 101640903 PMC - PMC6915459 OTO - NOTNLM OT - capacitive pressure sensor OT - carbon nanotubes OT - composite dielectric OT - percolation theory OT - printed and flexible sensor COIS- The authors declare no conflict of interest. EDAT- 2019/10/28 06:00 MHDA- 2019/10/28 06:01 PMCR- 2019/10/23 CRDT- 2019/10/27 06:00 PHST- 2019/08/30 00:00 [received] PHST- 2019/10/04 00:00 [revised] PHST- 2019/10/20 00:00 [accepted] PHST- 2019/10/27 06:00 [entrez] PHST- 2019/10/28 06:00 [pubmed] PHST- 2019/10/28 06:01 [medline] PHST- 2019/10/23 00:00 [pmc-release] AID - mi10110715 [pii] AID - micromachines-10-00715 [pii] AID - 10.3390/mi10110715 [doi] PST - epublish SO - Micromachines (Basel). 2019 Oct 23;10(11):715. doi: 10.3390/mi10110715.