Neuro‐Actuating Photonic Skin Enabled by Ion‐Gel Transistor with Thermo‐Adaptive Block Copolymer

Abstract Despite significant progress in developing artificial synapses to emulate the human nervous system for bio‐signal transmission, synapses with thermo‐adaptive coloration and soft actuators driven by temperature change have seldom been reported. Herein, a photonic neuro‐actuating synaptic skin is presented enabling thermoresponsive synaptic signal transmission, color variation, and actuation. First, a thermoresponsive display synapse is developed based on a 3‐terminal ion‐gel transistor with a poly (3,4‐ethylene dioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) semiconducting channel mixed with 2D titanium carbide (Ti3C2Tx) MXene and a thermo‐adaptive 1D block copolymer (BCP) photonic crystal (PC) gate insulator. Temperature‐dependent synaptic behavior is successfully observed in the ion‐gel transistor with the corresponding structural colors, leading to a thermo‐adaptive display synapse. The 3 × 3 arrays of thermo‐adaptive display synapses with Joule heaters show that each pixel is controlled by the thermoresponsive structural color and synaptic output. The synaptic output current from the MXene ion‐gel transistor can be converted and amplified to a voltage signal, which powers a soft actuator connected to the ion‐gel display synapse and triggers temperature‐dependent actuation related to the thermoresponsive synaptic performance. This study showcases a thermo‐adaptive photonic neuro‐actuating artificial skin that emulates muscle‐combined neuronal human skin with visualization capability.