3D-Printed PMN–PT/PDMS Piezoelectric Sensors with High Sensitivity for Intelligent Sensing

Piezoelectric sensors have attracted great attention owing to their capability of directly converting mechanical stimuli into electrical signals. The properties of piezoelectric materials and their manufacturing techniques significantly impact the performance of a piezoelectric sensor. Herein, a piezoelectric composite is developed by integrating PMN–PT ceramic particles with superior piezoelectric properties into a flexible PDMS polymer matrix, and piezoelectric sensors with patterned structures are successfully fabricated via direct ink writing (DIW) 3D printing. It was demonstrated that the PMN–PT/PDMS piezoelectric sensor achieved a maximum sensitivity of 914 mV·N1–, which is approximately twice the values obtained from previous related studies. Moreover, the sensor is sensitive to structural variations, making it feasible to tune the piezoelectric output. This work demonstrates that 3D-printed piezoelectric sensors with rational structural design enable a more sensitive perception of mechanical stimuli, providing a viable strategy for intelligent security identification and human motion detection.