Ultra‐Low‐Energy NbOI ₂ Synaptic Transistors for Neuromorphic Computing and Closed‐Loop Human‐Machine Interaction

ABSTRACT As the bottleneck of energy efficiency associated with the separation of storage and computation in the von Neumann architecture becomes increasingly restrictive, brain‐inspired electronic devices based on 2D materials are emerging as promising candidates for next‐generation information processing. Here, a top‐gate tri‐terminal optoelectronic synapse based on 2D NbOI 2 is demonstrated. Stable inhibitory postsynaptic current (IPSC) modulation and paired‐pulse depression (PPD) behaviors are successfully emulated for the first time in NbOI 2 devices. The device achieves an ultralow single‐spike energy consumption, comparable to that of natural biological synapses (∼10 fJ). Under hybrid optical‐electrical stimulation, it exhibits long‐term potentiation and depression (LTP/LTD), showing versatile synaptic plasticity. An artificial neural network constructed using its synaptic properties achieves classification accuracies of 93.61% and 84.57% on the MNIST and Fashion‐MNIST datasets, respectively. Furthermore, a closed‐loop human‐machine interaction system inspired by the vision‐neural‐motor pathway is established by exploiting the accumulative photocurrent memory of NbOI 2 synapses. Multi‐channel robotic arm control is also realized, highlighting the scalability of NbOI 2 optoelectronic synapses for complex collaborative tasks. This work demonstrates the dual potential of NbOI 2 optoelectronic synapses in neuromorphic computing and intelligent human‐machine interaction, offering insights for the development of energy‐efficient brain‐inspired electronics.