Fig. 1: Structure and design.

a Schematic of the fabrication procedure for the e-synapse with the Al2O3/GQDs/Al2O3 configuration. b AFM image of the GQDs deposited on Al2O3 and the section height profile. The inset presents a high-magnification AFM image. c TEM images of the GQDs. The inset presents a high-magnification image. d UPS spectra of the GQDs: cutoff region (top) and valence region (bottom). e The commonality between the e-synapse and the biological chemical synapse