Nanoweb structuring for enhanced ion doping efficiency and long-term plasticity of organic artificial synapses

Ion-gated organic synaptic transistors (IGOSTs) hold great potential for artificial synapses; however, achieving stable and reliable synaptic performance remains a significant challenge. Surface morphology modification, including channel porosity control, has emerged as a promising strategy to enhance IGOSTs performance by enabling precise regulation of ion permeation and transport. Yet, the impact of channel surface morphology on the electrical synaptic behaviors of IGOSTs remain unexplored, and its application in artificial synapses is notably underdeveloped. In this study, we developed a foaming-assisted nanoweb structuring approach to enhance ionic interactions and doping efficiency in IGOSTs. The expanded surface area of the nanoweb-structured organic semiconductors significantly improved ion doping efficiency. In addition, the enhanced crystallinity induced by chain stretching and ordered alignment formed during the foaming process effectively suppressed ion back-diffusion, resulting in the improved long-term plasticity (LTP), and linearity in long-term potentiation/depression (LTP/D). These findings reveal the dual role of channel morphology modification in synaptic regulation and provide a design strategy for optimizing IGOSTs in neuromorphic computing applications.