Humidity-Responsive dBSA-MoS ₂ Nanocomposite Film Assembled via Liquid–Liquid Interface for Simulating Artificial Synaptic Behavior

Von Neumann architectures face inherent limitations, prompting the rise of neuromorphic computing as a promising alternative. Artificial synapses play a crucial role in replicating the dynamic plasticity of biological synapses, enabling efficient information processing and adaptive learning. We developed a composite nanofilm device composed of denatured bovine serum albumin (dBSA) and molybdenum disulfide (MoS2) using a liquid–liquid interfacial assembly technique. The dBSA-MoS2 current response to humidity is 13.12 times higher than that of pure MoS2. At a relative humidity of 80%, the dBSA-MoS2 device exhibits more pronounced negative differential resistance and hysteresis phenomena than pure MoS2, and the resistance switching ratio of the dBSA-MoS2 device is 3.20- and 2.64-fold higher than those of MoS2 at 0.72 and 1.52 V, respectively. The incorporation of dBSA creates additional pathways for proton transport, which not only improves the electrical properties of dBSA-MoS2 but also enables it to emulate biological synaptic functions. Consequently, the dBSA-MoS2 device was used to simulate the biological synaptic behaviors: long-term potentiation and long-term depression. When integrated into a three-layer artificial neural network for handwritten number recognition, the dBSA-MoS2 device achieved an impressive accuracy of 92.30%. These findings underscore the potential of dBSA-MoS2 composites as next-generation artificial synapses, offering significant promise for neuromorphic computing and future bioelectronic applications.