Piezoresistive Graphene/P(VDF-TrFE) Heterostructure Based Highly Sensitive and Flexible Pressure Sensor

Soaram Kim; Yongchang Dong; Md Maksudul Hossain; Sean Gorman; Itmenon Towfeeq; Durga Gajula; Anthony Childress; Apparao M Rao; Goutam Koley

doi:10.1021/acsami.9b01964

Piezoresistive Graphene/P(VDF-TrFE) Heterostructure Based Highly Sensitive and Flexible Pressure Sensor

ACS Appl Mater Interfaces. 2019 May 1;11(17):16006-16017. doi: 10.1021/acsami.9b01964. Epub 2019 Apr 18.

Authors

Soaram Kim¹, Yongchang Dong, Md Maksudul Hossain, Sean Gorman, Itmenon Towfeeq, Durga Gajula, Anthony Childress, Apparao M Rao, Goutam Koley

Affiliation

¹ Department of Electrical and Computer Engineering , University of Maryland , College Park , Maryland 20742 , United States.

PMID: 30964640
DOI: 10.1021/acsami.9b01964

Abstract

We report on a novel graphene/P(VDF-TrFE) heterostructure based highly sensitive, flexible, and biocompatible pressure/strain sensor developed through a facile and low-cost fabrication technique. The high piezoelectric coefficient of P(VDF-TrFE) coupled with outstanding electrical properties of graphene makes the sensor device highly sensitive, with an average sensitivity of 0.76 kPa^-1, a gauge factor of 445, and signal-to-noise ratio of 60.8 dB in the range of pressure up to 45 mmHg. A model was proposed to explain the sensor operation, based on carrier density and mobility changes induced by the piezoelectric charge generated in response to strain, which was supported by Hall measurements and Raman spectroscopy. Potential applications in wearable sensing for human activity monitoring were also demonstrated.

Keywords: P(VDF-TrFE); PDMS; flexible; piezoresistive; pressure sensor; strain.