The effect of the PVA hydrolysis degree on the electrical properties of organic resistive memories based on PVA plus CNT composites

This work studies the interaction effect between functionalized multiwall carbon nanotubes (f-CNTs) and a polymeric matrix in the electrical behavior of resistive memories. f-CNTs were synthesized by spray pyrolysis using xylene-ethanol (1:0.8 v/v) as the reaction mixture, allowing the in-situ functionalization (OH, COOH, C-H, C-OH groups) on the f-CNT surface and, then, improving their solubility in polar solvents as well as their dispersion in a polymeric matrix. Two types of polyvinyl alcohol (PVA) with different hydrolysis degrees were used, PVA with high hydrolysis (HD) degree (Mw 89,000-98,000, 99 + % hydrolyzed) and PVA with low hydrolysis (LD) degree (Mw 9000-10,000, 80% hydrolyzed), for the fabrication of the organic resistive memories. The PVA + f-CNT composites show significant differences in the morphology, thickness and current-voltage (I-V) electrical behavior as a function of the hydrolysis degree of the PVA matrix. In the case of I-V measurements, our results are broadly different from those reported in the literature, PVA-LD + f-CNT composites at 1, 3 and 5 wt% f-CNTs show rewritable behavior, whereas PVA-HD + f-CNT composites the rewritable behavior started at 5 wt%. From here, we conclude that the polymeric matrix can play an essential role in the resistive memory behavior.

Automated summary

This work investigates the influence of the interaction between functionalized multiwall carbon nanotubes (f-CNTs) and a polymeric matrix on the electrical behavior of resistive memories. The findings suggest that the hydrolysis degree of the polymeric matrix plays a crucial role in the morphology, thickness, and current-voltage behavior of the PVA + f-CNT composites.