Graphical Abstract

Neurologic function implemented soft organic electronic skin holds promise for wide range of applications, such as skin prosthetics, neurorobot, bioelectronics, human-robotic interaction (HRI), etc. Here, we report the development of a fully rubbery synaptic transistor which consists of all-organic materials, which shows unique synaptic characteristics existing in biological synapses. These synaptic characteristics retained even under mechanical stretch by 30%. We further developed a neurological electronic skin in a fully rubbery format based on two mechanoreceptors (for synaptic potentiation or depression) of pressure-sensitive rubber and an all-organic synaptic transistor. By converting tactile signals into Morse Code, potentiation and depression of excitatory postsynaptic current (EPSC) signals allow the neurological electronic skin on a human forearm to communicate with a robotic hand. The collective studies on the materials, devices, and their characteristics revealed the fundamental aspects and applicability of the all-organic synaptic transistor and the neurological electronic skin.
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