Intrinsically stretchable organic electrochemical synaptic transistors for versatile response modulations

Abstract

The development of intrinsically stretchable organic electrochemical synaptic transistors (ISOESTs) based entirely on elastomeric materials is pivotal for advancing applications requiring neuromorphic functionality under significant mechanical deformation. This study presents ISOESTs capable of replicating a comprehensive range of synaptic behaviors, including excitatory postsynaptic currents (EPSCs), paired-pulse facilitation (PPF), and transitions from short-term memory (STM) to long-term memory (LTM). Remarkably, these synaptic characteristics were preserved even when the devices were subjected to 30% uniaxial strain, demonstrating exceptional mechanical robustness and functional stability. A pixelated 5 × 5 array of ISOESTs exhibited minimal device-to-device variation, underscoring the scalability and uniformity of the fabrication approach. To further illustrate their potential, a neurologically integrated electronic skin (e-skin) was fabricated, incorporating these ISOESTs to enable modulation of synaptic responses. The modulation of synaptic responses was strongly correlated with electrochemical analyses, establishing a robust operational framework for programmable neuromorphic systems. Comprehensive investigations into device fabrication, operation mechanisms, and integration strategies provide critical insights into the potential of these systems for next-generation applications in wearable electronics, soft robotics, neuro-prosthetics, and human–machine interfaces. This work represents a significant step toward realizing adaptive, biologically inspired electronic platforms capable of bridging the gap between engineered systems and living tissues.