High performance piezocomposites for flexible device application

Abstract

Flexible piezocomposites have emerged as promising materials for highly durable wearable devices. Here, we propose a new design strategy, namely particle alignment engineering, to develop high performance flexible piezocomposites by dielectrophoresis (DEP). An ultrahigh piezoelectric voltage coefficient (g₃₃) of 600 × 10⁻³ V m N⁻¹ is achieved by a composite of (Ba_0.85Ca_0.15)(Ti_0.90Zr_0.10)O₃ (BCZT) particles aligned in a polydimethylsiloxane (PDMS) matrix. To the best of our knowledge, this g₃₃ value is by far the highest ever achieved in piezocomposites. The significantly improved poling electric voltage applied to the BCZT particles and hugely enhanced stress-transfer capability of the aligned composite synergistically contribute to the record-high piezoelectric response in flexible piezocomposites. The fabricated flexible piezoelectric touch sensor and wearable keyboard possess an excellent sensitivity and cycling stability, which demonstrate a promising strategy for exploring high performance piezocomposites for flexible device application.