PMID- 34569100
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20211201
IS  - 1521-4095 (Electronic)
IS  - 0935-9648 (Linking)
VI  - 33
IP  - 48
DP  - 2021 Dec
TI  - Highly Sensitive Capacitive Pressure Sensors over a Wide Pressure Range Enabled 
      by the Hybrid Responses of a Highly Porous Nanocomposite.
PG  - e2103320
LID - 10.1002/adma.202103320 [doi]
AB  - Past research aimed at increasing the sensitivity of capacitive pressure sensors 
      has mostly focused on developing dielectric layers with surface/porous structures 
      or higher dielectric constants. However, such strategies have only been effective 
      in improving sensitivities at low pressure ranges (e.g., up to 3 kPa). To 
      overcome this well-known obstacle, herein, a flexible hybrid-response pressure 
      sensor (HRPS) composed of an electrically conductive porous nanocomposite (PNC) 
      laminated with an ultrathin dielectric layer is devised. Using a nickel foam 
      template, the PNC is fabricated with carbon nanotubes (CNTs)-doped Ecoflex to be 
      86% porous and electrically conductive. The PNC exhibits hybrid piezoresistive 
      and piezocapacitive responses, resulting in significantly enhanced sensitivities 
      (i.e., more than 400%) over wide pressure ranges, from 3.13 kPa(-1) within 0-1 
      kPa to 0.43 kPa(-1) within 30-50 kPa. The effect of the hybrid responses is 
      differentiated from the effect of porosity or high dielectric constants by 
      comparing the HRPS with its purely piezocapacitive counterparts. Fundamental 
      understanding of the HRPS and the prediction of optimal CNT doping are achieved 
      through simplified analytical models. The HRPS is able to measure pressures from 
      as subtle as the temporal arterial pulse to as large as footsteps.
CI  - (c) 2021 Wiley-VCH GmbH.
FAU - Ha, Kyoung-Ho
AU  - Ha KH
AD  - Department of Mechanical Engineering, University of Texas at Austin, Austin, TX, 
      78712, USA.
FAU - Zhang, Weiyi
AU  - Zhang W
AD  - Department of Aerospace Engineering and Engineering Mechanics, University of 
      Texas at Austin, Austin, TX, 78712, USA.
FAU - Jang, Hongwoo
AU  - Jang H
AD  - Texas Material Institute, University of Texas at Austin, Austin, TX, 78712, USA.
FAU - Kang, Seungmin
AU  - Kang S
AD  - Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 
      78712, USA.
FAU - Wang, Liu
AU  - Wang L
AD  - Department of Aerospace Engineering and Engineering Mechanics, University of 
      Texas at Austin, Austin, TX, 78712, USA.
FAU - Tan, Philip
AU  - Tan P
AD  - Department of Electrical and Computer Engineering, University of Texas at Austin, 
      Austin, TX, 78712, USA.
FAU - Hwang, Hochul
AU  - Hwang H
AD  - Department of Aerospace Engineering and Engineering Mechanics, University of 
      Texas at Austin, Austin, TX, 78712, USA.
FAU - Lu, Nanshu
AU  - Lu N
AUID- ORCID: 0000-0002-3595-3851
AD  - Department of Aerospace Engineering and Engineering Mechanics, Department of 
      Electrical and Computer Engineering, Department of Mechanical Engineering, 
      Department of Biomedical Engineering, Texas Materials Institute, University of 
      Texas at Austin, Austin, TX, 78712, USA.
LA  - eng
GR  - N00014-20-1-2112/Office of Naval Research/
GR  - N00014-18-1-2323/Office of Naval Research/
GR  - W911NF-19-2-0333/Army Research Office/
PT  - Journal Article
DEP - 20210927
PL  - Germany
TA  - Adv Mater
JT  - Advanced materials (Deerfield Beach, Fla.)
JID - 9885358
SB  - IM
OTO - NOTNLM
OT  - conductive foams
OT  - e-skins
OT  - flexible electronics
OT  - porous nanocomposites
OT  - pressure sensors
OT  - pulse waveforms
EDAT- 2021/09/28 06:00
MHDA- 2021/09/28 06:01
CRDT- 2021/09/27 06:35
PHST- 2021/07/27 00:00 [revised]
PHST- 2021/04/30 00:00 [received]
PHST- 2021/09/28 06:00 [pubmed]
PHST- 2021/09/28 06:01 [medline]
PHST- 2021/09/27 06:35 [entrez]
AID - 10.1002/adma.202103320 [doi]
PST - ppublish
SO  - Adv Mater. 2021 Dec;33(48):e2103320. doi: 10.1002/adma.202103320. Epub 2021 Sep 
      27.