A printable P(VDF-TrFE)-PZT Composite with Very High Piezoelectric Coefficient

Abstract In this paper a significant advance in the piezoelectric properties of poly(vinylidenefluoride-trifluoroethylene)-lead zirconate titanate (P(VDF-TrFE)-PZT) composite ink has been achieved by coating the ceramic particles prior to formulation with a polymeric surfactant containing carboxylic acid anhydride functional groups and the piezoelectric response of a unimorph cantilever is further enhanced by introducing a reinforced substrate. The measured effective transverse piezoelectric coefficient (d31eff) was -56 pm/V, which is 3.3 times higher than that of the same composite without surfactant and is the highest reported for a printable polymer-ceramic composite. In addition, the printability of the ink and dispersion of the ceramic particles was enhanced. The samples were fabricated by stencil printing of a single piezoelectric layer on a flexible PET substrate followed by curing at only 120°C, thus enabling utilization on a wide range of substrates. The results also show the improved particle dispersion and layer quality in 0-3 composite inks with surfactant added and the effect of sample structure and mechanical coupling between the hard ceramic particles and the soft matrix. The developed composite ink is suitable, for example, in sensors in printed wearable and portable electronics.