Detachable and Reusable: Reinforced π‐Ion Film for Modular Synaptic Reservoir Computing

Organic electrochemical transistors (OECTs) show significant promise for bioelectronics and neuromorphic computing applications due to their low operating voltage, biocompatibility, and ion‐mediated charge transport. However, conventional OECTs with permanently fixed organic semiconductor (OSC) layers lack modularity and reusability for sustainable electronics with e‐waste reduction. Here, a novel reinforced π‐ion film OECT featuring a detachable and reusable OSC layer that creates a unified composite with dielectric and gate components, establishing a new paradigm for modular device architectures is proposed. Through solvent exchange and mesh‐supported gelation, π‐ion film exhibits enhanced mechanical stability, detachability, and superior electrical performance. The OECTs demonstrate remarkable 35‐day air stability, 50‐day storage lifetime, and over 80% performance retention after 600 electrical cycles. Furthermore, the π‐ion film OECTs exhibit synaptic behavior with paired‐pulse facilitation of 167% and long‐term memory retention of 34% maintained synaptic current after 250 s. These characteristics enable reservoir computing applications with a 4‐bit encoding scheme for image recognition, processing 16 × 16 pixelated input patterns, demonstrating reliable state differentiation and stable signal retention. Even at lab‐scale development, reinforced π‐ion film OECTs represent a promising eco‐friendly platform for modular, reusable components in next‐generation neuromorphic computing systems, aligning with electronic waste reduction policies by enabling component reuse.