Highly Sensitive Dual-Mode Touch Sensing Device Using Poly(vinylidene fluoride)/Graphene Nitride for Wearable E-Skin: Patterning, High-Temperature Annealing, and Remote Data Transmission

In recent years, significant advancements in printed electronics and flexible materials have catalyzed the development of electronic skins for wearable applications. However, the low glass transition temperature of flexible substrates poses a challenge as it is incompatible with the high-temperature annealing required for electrode fabrication, thereby limiting the performance of flexible electronic devices. In this study, we address these limitations by proposing a novel flexible device manufacturing process that combines adhesive printing patterning with a transfer printing technology. By employing poly(vinylidene fluoride) (PVDF)/graphene nitride (GCN) as the transfer substrate and dielectric layer, we successfully fabricated a high-performance dual-mode touch sensor on a large scale. The successful development of this dual-mode sensor can be attributed to two key factors: the construction of a robust hydrogen-bonding network between the PVDF/GCN dielectric layer and the carbon electrode and the ability of GCN to restrict the movement of PVDF molecular chains within the dielectric layer. This restriction reduces the overall polarization of the film, enabling the formation of a complete device structure with a highly sensitive edge electric field. The noncontact sensors developed in this study are fully printable into sensor arrays and can be seamlessly integrated with internet of things technology for wearable applications. These sensors exhibit exceptional tactile response and facilitate effective human-machine interactions over extended distances, underscoring their significant potential in fields such as healthcare and artificial intelligence.