Transient piezoresistive sensors based on tolerable, safe, and semiconductive polypyrrole/vermiculite/alginate frameworks

The rapid development of flexible pressure sensors is driven by the fields of electronic skin, human–machine interaction, and health monitoring. These sensors are urgently required. However, it is challenging to simultaneously meet their durable and transient requirements. In this study, a safe and tolerant polypyrrole/vermiculite/alginate semiconductive framework is developed for flexible transient piezoresistive sensors. Negatively charged vermiculite nanosheets are interlayered into biodegradable alginate fabrics, which are further decorated with conductive polypyrrole. The developed multidimensional framework ensures stability for flexible sensors and can be gradually degraded without producing e-waste after completing its service life. The obtained transient piezoresistive sensors exhibit rapid response/recovery time (81/99 ms) and outstanding fatigue resistance properties. Furthermore, an effective machine learning model is developed for human motion recognition and prediction, achieving 100% accuracy. This study provides a promising strategy for organic–inorganic interface design in flexible transient electronics and shows broad application prospects in flexible platforms based on comfortable biofibers.