Neurotransmitter ligand effect of dopamine and cortisol conjuation on ZnO nanoparticles embedded polyvinylphenol resistive switching device

Abstract

In this paper, dopamine (DA) and cortisol (CORT), two kinds of neurotransmitters, were adopted as a ligand or surface modification agent on zinc oxide (ZnO) nanoparticles (NPs) to modulate resistive switching (RS) property of the ZnO NPs embedded into polyvinylphenol (PVP) hybrid matrix. Here, digital and analog RS behaviors were demonstrated with the DA and CORT conjugations showing different ligand influence on the RS properties, respectively. For the hybrid layer, operations of bistable ON/OFF and multileveled resistance or conductance could coexist depending on the thickness and concentration of the ZnO NPs. First, conjugation of the DA on the ZnO NPs could reveal distinct memristive behaviors, which demonstrated potentiation of analog RS mode by showing gradually increased windows of the I–V hysteresis by consecutive sweeps, which were distinguished from the unconjugated ZnO NPs embedded PVP device. Secondly, in the other hand, conjugation of the CORT as the ZnO NPs’ ligand could demonstrate enhanced depression characteristics unlike the potentiation behavior induced by the DA conjugation. Therefore, since the biological neurotransmitters of DA and CORT were found to influence the RS behaviors, a novel development of bioelectronic neuromorphic device implemented for a direct interface between biological neuro-system and electronic RS device can be envisioned through this study.