High-Sensitivity, Broad-Range Pressure Sensing via a Molecular Piezoelectric Sponge

Piezoelectric pressure sensors have attracted considerable interest owing to their high sensitivity, dynamic pressure detection capability, and self-powered operation, enabling broad applications in healthcare monitoring, soft robotics, and human-machine interaction (HMI). However, current piezoelectric sensors fall short in spanning the multiscale pressures generated by human motion. Here, we report a self-powered piezoelectric pressure sensor constructed by integrating the molecule-based piezoelectric compound [(CH 3 ) 3 NCH 2 CH 2 Br]GaBr 4 ( 1 ) into a three-dimensional porous PDMS sponge fabricated via a sucrose-templating strategy. The synergistic interplay between compound 1 and the porous elastomeric framework endows the sensor with high sensitivity (0.64 V·kPa –1 below 50 kPa), ranking third among molecule-based piezoelectric sensors, and the broadest monitoring range reported to date for such sensors, extending up to 300 kPa. As a result, the device enables precise detection of subtle motions such as gripping and joint bending (below 100 kPa), as well as dynamic activities including walking, running, and jumping (above 100 kPa). These findings highlight its strong potential for practical applications in wearable electronics and human-machine interaction systems.