Investigations on the preparation and properties of high-sensitive BaTiO3/MwCNTs/PDMS flexible capacitive pressure sensor

Abstract

In this paper, a flexible capacitive pressure sensor with porous barium titanate (BaTiO3)/multi-walled carbon nanotubes (MwCNTs)/polydimethylsiloxane (PDMS) composite layer as the dielectric layer was fabricated. The sensitivity, stability, response time and human compatibility of the sensor were fully studied. The results showed that a controllable porous microstructure dielectric layer was built successfully where hybrid BaTiO3 and MwCNTs fillers with giant permittivity distributed homogeneously. The BaTiO3/MwCNTs/PDMS flexible capacitive pressure sensor possessed high sensitivity (~1.24 kPa−1) and good stability in the low pressure range (0 ~ 0.8 kPa). Moreover, a low detection limit (~7 Pa) and a fast response time (~200 ms) were obtained. Human compatibility test revealed that our flexible sensor could catch the response of human body swiftly so that it exhibited a bright application prospect in wearable electronics.