Enhancing the Performance of Flexible BCZT NWs/PDMS Piezoelectric Sensor by Doping Ce ³⁺ Ions Into BCZT Nanowires

Abstract Lead‐free and environmentally friendly ceramic materials have been attracted extensive attention in flexible piezoelectric devices. In this work, a series of Ce ³⁺ doped Ba _0.85 Ca _0.15 Zr _0.1 Ti _0.9 O ₃ (BCZT‐ x Ce ³⁺ ) nanowires (NWs), with different molar ratios of Ce ³⁺ to BCZT ( x ), are synthesized using a two‐step hydrothermal reaction method with HZTO NWs as a precursor. Flexible composites are prepared by dispersing BCZT‐ x Ce ³⁺ NWs into polydimethylsiloxane (PDMS) matrix. The BCZT‐0.001 Ce ³⁺ NWs/PDMS composite is found to have a piezoelectric coefficient ( d ₃₃ ) as high as 223.2 pC·N ⁻¹ , which is 393% higher than that of the pure BCZT NWs/PDMS composite. The BCZT‐0.001 Ce ³⁺ NWs/PDMS composite shows the optimal sensing properties with output open‐circuit voltage and short‐circuit current of 9.04 V and 53 nA, respectively, which is significantly higher than that of the BCZT NWs/PDMS composite. Moreover, the sensor features a voltage – pressure linearity in the ultra‐wide pressure range of 2.22 to 155.56 kPa, with sensitivity of 0.0565 V·kPa ⁻¹ , and a good durability over 10 000 cycles. Further demonstration shows that the sensor is suitable for monitoring human motion at low‐frequency such as 2 Hz, with an ultra‐fast response time of ≈120 ms, making it a promising candidate for applications in the fields of human health monitoring and artificial intelligence.