Achieving enhanced piezoelectric performance in three-dimensional interconnected BCZT piezoelectric porous ceramics

Piezoelectric ceramics are widely used in the field of sensors due to their ability to sensitively respond to minor stimuli. (Ba_0.85Ca_0.15)(Zr_0.1Ti_0.9)O₃ (BCZT) piezoelectric ceramics have attracted extensive attention in the sensing field due to their high piezoelectric charge coefficient (d₃₃). However, the strong coupling between d₃₃ and the dielectric constant (ε_r) can degrade the sensing performance. In this study, BCZT porous ceramics with three-dimensionally interconnected pore structure were fabricated using the foam-gelcasting method. The introduction of pores leads to a simultaneous decrease in both d₃₃ and ε_r. Due to the greater reduction in ε_r, the piezoelectric voltage coefficient (g₃₃) has an upward trend, achieving the decoupling of the d₃₃ and ε_r. The piezoelectric voltage coefficient reached 181 × 10⁻³ V·m·N⁻¹, the with sensitivity of 56.1 V/kPa and the response time of 0.27 s, respectively. This research provides a widely applicable alternative porous material for piezoelectric sensors.