Realization of Precise Human Gesture Recognition via a Self‐Powered Flexible Sensor Based on Thermal Expansion‐Treated and Potassium Ion‐Modified VMT/PDMS Film
Yukai Zhang, Mingcong Tang, Chengyu Chen, Yuxin Shi, Weijin Wang, Zhaofeng Wu
Abstract
Abstract 2D materials hold significant promise for piezoelectric nanogenerator applications, yet scalable fabrication remains hindered by technical challenges. This study introduces an innovative approach by leveraging natural layered silicate vermiculite (VMT) as the functional material. Through systematic investigations combining thermal expansion and metal ion intercalation, elucidate the interplay between structural expansion, ionic modification, and piezoelectric voltage output. Notably, K + ‐intercalated expanded VMT (K‐VMT) demonstrates a remarkable output voltage of 20 V—nearly triple that of unmodified counterparts—underscoring its superior efficacy as a piezoelectric sensing layer. Building on this advancement, a flexible self‐powered piezoelectric sensor is fabricated using a K‐VMT/polydimethylsiloxane (PDMS) composite. The device exhibits exceptional mechanical stability and flexibility, achieving a low detection limit of 0.01 N. Real‐time human motion tracking, pressure gradient discrimination, and gesture recognition capabilities are demonstrated, and different gestures are recognized through the feature extraction framework of 1D multi‐granularity convolution, and the recognition rate can reach 99.86%. This work not only expands the application scope of 2D materials in piezoelectric sensing but also establishes a cost‐effective, eco‐friendly pathway for high‐performance flexible devices. The integration of abundant natural minerals with scalable processing techniques represents a transformative strategy for next‐generation energy‐autonomous sensors.