Robust and Wearable Pressure Sensor Assembled from AgNW-Coated PDMS Micropillar Sheets with High Sensitivity and Wide Detection Range

Polydimethysiloxane (PDMS)-based materials are emerging as an ideal category of flexible multifunctional membranes that are expected to be used for wearable and skin-attachable pressure sensors. Here, we report a simple and effective fabrication strategy to construct a highly sensitive and robust wearable pressure sensor device based on interlocked connection structure (ILCS), which formed from silver nanowires (AgNW)-coated PDMS pillar arrays sheets. Two pieces of PDMS thin layers that manufactured with AgNW-coated pillar arrays were assembled face to face as the pressure sensing device. The interlocked structures enable a pressure sensitive variation in the contact area between AgNW-coated PDMS pillars under different pressure loading. Therefore, the electrical resistance changes according to the degree of interconnection and pillar deformation when different magnitudes of pressures were applied. The pressure sensor exhibits ultrahigh pressure sensitivity of similar to 20.08 kPa(-1) up to 0.8 kPa, and sensor response is highly reproducible and repeatable for more than 10000 cycles. Additionally, all the results demonstrate that the pressure sensor can be used as the device for the monitoring of the signals ranging from epidermis movements to air flows, such as mimic swallowing action, gently touching, bending, and torsion. We believe that the presented sensor can be used in many potential applications fields, such as flexible electronics, artificial e-skin, wearable sensor devices, and so on.