Mesh-Architected Structurally Flexible Pb(Zr<sub>0.52</sub>Ti<sub>0.48</sub>)O<sub>3</sub> Framework Enables Highly Sensitive and Stretchable Piezoelectric Sensors.

Abstract

The booming demand for flexible electronics requires piezoelectric sensors that can simultaneously deliver high sensitivity and exceptional stretchability, which has become a significant challenge beyond the capabilities of conventional devices. Inspired by the hexagonal mesh structure, we adopted an architecture design to fabricate a continuous, structurally flexible ceramic skeleton, thereby developing a piezoelectric sensor integrating both high sensitivity and superior stretchability. The macroscopic 3D interconnected skeleton ensures efficient stress transfer for enhanced pressure sensitivity, while the hexagonal topology with hierarchical microfibers enables deformation-driven slippage under load to ensure robust stretchability. Consequently, the composite achieves remarkable stretchability (220% strain) and excellent mechanical stability (> 50 stretch-compression cycles, hysteresis ~ 8.13%). The fully flexible piezoelectric sensor maintains stable functionality even under 100% tensile strain and exhibits high sensitivity (39.57 mV kPa^-1), collectively outperforming conventional piezoelectric sensors. Based on these unique advantages, we demonstrate the sensor's capability in fine surface roughness discrimination and real-time monitoring of human stretching movements, highlighting its great potential for applications in robotic dexterous manipulation and wearable health monitoring systems.