Flexible Piezoelectric and Piezoresistive Mechanisms Coupled Sensor for Highly Dynamic and Static Collaborative Detection

Flexible sensors have emerged and gained popularity in recent years due to their potential in electronic skin, medical care and other fields. However, single mechanism sensor shows great limitation in the cooperative monitoring of highly dynamic and static detection, which limits further practical applications seriously. This paper reports a strategy that combines piezoelectric and piezoresistive mechanisms for the realization of dual function in a single flexible sensor. Piezoelectric unit based on PVDF polymer is used for highly dynamic detection while piezoresistive cell composed of graphite sheet (GS) and PVDF electrospun mat is for static detection. Besides, this dual mechanism flexible sensor (DMFS) exhibits a higher piezoelectric sensitivity than the individual PVDF piezoelectric sensor due to the fact that the introduction of soft piezoresistive layer increases the transverse strain on the piezoelectric layer originated from large deformation of the low stiffness surface.