The fourth industrial revolution indispensably brings explosive data processing and storage; thus, a new computing paradigm based on artificial intelligence-enabling device structure is urgently required. Memristors have received considerable attention in this regard because of their ability to process and store data at the same location. However, fundamental problems with abrupt switching characteristics limit their practical application. To address this problem, we utilized the concept of metaplasticity inspired by biosystems and observed gradual switching in the peptide-based memristor at high proton conductivity. An unexpectedly high slope value > 1.7 in the logI–V curve at low voltage (≤ 400 mV) was considered the main origin, and it might arise from the modulatory response of proton ions on the threshold of Ag ion migration in the peptide film. With the obtained gradual switching property at high proton conductivity, the device showed significantly increased accuracy of image recognition (~ 82.5%). We believe that such a demonstration not only contributes to the practical application of neuromorphic devices but also expands the bioinspired functional synthetic platform.

Electrical and optical enhancements of single-layer semiconducting materials such as transition metal dichalcogenides have recently been studied to achieve sensitive properties via external treatments, such as the formation of organic/inorganic protecting layers on field-effect transistors (FETs), thermal annealing, and nano-dot doping of sensors and detectors. Here, we propose a new analytical approach to electrical and optical enhancement through a passivation process using atomic layer deposition (ALD), and demonstrate a synthesized MoS₂ monolayer incorporated with Al atoms in an Al₂O₃ passivation layer. The incorporated Al atoms in the MoS₂ monolayer are clearly observed by spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM) and TEM-energy-dispersive X-ray spectroscopy results. We demonstrate that the chemically incorporated FETs exhibit highly enhanced mobilities of approximately 3.7 cm²·V^-1·s^-1, forty times greater than that of as-synthesized MoS₂, with a three-fold improvement in the photoluminescence properties.