Improved ternary memory performance of donor–acceptor structured molecules through cyano substitution

Abstract

Organic memory devices can greatly increase the data-storage density and have attracted significant attention in recent years. Thus, two small molecules, DPHCANA and DPCNCANA, were designed and successfully synthesized to investigate the improvement of memory devices through introducing the strong electron withdrawing cyano group on the central phenyl ring. It is noteworthy that DPCNCANA with a cyano group exhibited excellent ternary memory behavior, benefiting from induced intermolecular H-bond connection and layer by layer molecular stacking in the film state, which counteracted the higher hole transport barrier lying between the film and the bottom electrode. In addition, we have also found that the additional cyano group substitution lowered the LUMO energy level, which is favorable for the stability in air ambient circumstances. We envisage that this study will be very useful for the rational design of advanced next-generation semiconductor materials.