US EPA

7039561 

Journal Article 

Flexible piezoelectric pressure sensor based on polydopamine-modified BaTiO3/PVDF composite film for human motion monitoring 

Yang, Ye; Pan, H; Xie, G; Jiang, Y; Chen, C; Su, Y; Wang, Y; Tai, H; , 

2020 

1 

Sensors and Actuators A: Physical
ISSN: 0924-4247
EISSN: 1873-3069 

ELSEVIER SCIENCE SA 

LAUSANNE 

301 

10.1016/j.sna.2019.111789 

WOS:000514215300006 

Flexible pressure sensors based on piezoelectric materials have been intensively investigated for their wide applications in wearable electronics. However, traditional films based on inorganic/organic composite piezoelectric materials face the bottleneck of defects and cracks or poor dispersion, which hinders the performance of pressure sensors. Herein, polydopamine (PDA) was introduced as a surface modification agent to modify barium titanate (BaTiO3, BTO), which was then blended with poly(vinylidene fluoride) (PVDF) matrix in different ratios to form uniform and homogeneous PDA@BTO/PVDF composites. Afterwards, the flexible piezoelectric pressure sensor was fabricated by a facial solution-casting method. This PDA-modification strategy can improve the dispersion of BTO into PVDF matrix, as well as reduce the interface hole defects and cracks between the two components. As a result, the 17 wt% PDA@BTO/PVDF sensor exhibited a fast response of 61 ms and a remarkable piezoelectric output voltage of 9.3 V, which showed obvious improvement as compared to the pristine PVDF and BTO/PVDF composite counterparts. In addition, as an energy supplier, the sensor could produce a maximum power of 0.122 mu W/cm(2) even with high load resistance of 70 m Omega. This pressure sensor was sensitive to various human motions, showing great potential in the applications of wearable electronics. (C) 2019 Elsevier B.V. All rights reserved. 

PDA@BTO/PVDF; Piezoelectric; Pressure sensor; Flexible; Motion monitoring