Merkel cell-like artificial mechanoreceptor with high sensitivity and high resolution over a wide linear range
Jing Yang, Zhibin Li, Xu Zhang, Bin Chen, Jiansong Feng, Taihong Wang
Abstract
Mammalian mechanoreceptors endow the skin with the ability to perceive mechanical stimuli with precision. However, the fabrication of artificial mechanoreceptors with high sensitivity and resolution over a wide linear pressure range remains a key challenge. Herein, an artificial ion mechanoreceptor with the core-shell structured nanofibrous membrane as the sensitive layer is proposed by mimicking the biomechanical receptor. The membrane embeds ionic liquids and poly(vinylidene fluoride-co-hexafluoropropylene) hybrid nanofibers into a thermoplastic polyurethane matrix, enabling a reversible conversion between non-ionic and iontronic sensing modes induced by tactilely triggered ion movements. It exhibits a high sensitivity (32.70 kPa−1), a linear response (R2 ≈ 0.999) over a wide range of 0.04 Pa to 209 kPa, and an ultra-high resolution of 0.035% at 100 kPa (far exceeding the resolution of skin of ∼7%). The receptors are further used to monitoring physiological signals (even weak fingertip pulse signals) and assembled into an array to aid object recognition.