A Sensitive and Flexible Poroelastic Barium Titanate Matrix for Pressure Sensing Applications

This letter reports on poroelastic barium titanate matrix (PBM) for flexible pressure sensor applications. The fabrication of PBM is a simple and cost-effective process that allows an optimized composition of polydimethylsiloxane (PDMS) and barium titanate (BTO) to penetrate through the sugar template via capillary action. The fabricated PBM undergoes large deformation if compared to the state-of-the-art pressure sensors. Around a two-fold increase in sensitivity is observed with the appropriate weight percent (%) of BTO in PDMS and the %porosity in the PBM structure. The PBM generates a peak voltage of ∼1.1 V, whereas the nonporous composite (BTO+PDMS) generates only ∼500 mV. The response of PBM is highly linear (coefficient of linearity 0.983) and repeatable with a deviation of 0.47%. Furthermore, the operating range of PBM is 5–100 kPa. Finite element simulations are carried out to find the relation between the substrate porosity, %weight ratio of BTO, and the generated voltage. The optimized PBM can be exploited for applications, such as gait biomechanics.