A Retina‐Inspired Organic Iono‐Optoelectronic Synapse

ABSTRACT Retina‐inspired neuromorphic systems require seamless integration of light sensing and adaptive synaptic modulation, yet conventional materials fail to integrate ionic charge transport with optoelectronic signal processing. Organic iono‐optoelectronic devices offer a promising solution by coupling the optoelectronic properties of conjugated polymers with ionic and electronic transport. Here, we present an organic iono‐optoelectronic synapse enabled by a p‐type mixed ionic‐electronic conductor (OMIEC). The OMIEC material, gDPP‐MeOT2, a donor‐acceptor polymer comprising a thiophene‐flanked diketopyrrolopyrrole acceptor and methoxy‐bithiophene donor, serves simultaneously as a light absorber and an ion reservoir, enabling light‐modulated mixed charge transport. Our iono‐optoelectronic synapse exhibits broad‐band light detection spanning the visible to near‐infrared range and synaptic plasticity features central to learning processes of the human brain. These results suggest that OMIECs can unify light detection, logic operation, and energy‐efficient information processing, paving the way for next generation biohybrid vision systems and bio‐inspired neuromorphic electronics.