Rational introduction of functional spacers to realize a novel organometallic polymer with multilevel memory behaviors†

Multilevel resistive random access memory (ReRAM) has been well researched recently to meet the ever-growing data-storage requirements. However, the proposed mechanisms such as charge trap and charge transfer are highly dependent on molecular stacking regularity. Thus, improving the molecular stacking styles is a scientific issue that needs to be solved urgently. In this work, a modified organometallic conjugated polymer P(DTPDI-BDT-DPFc) was rationally designed with the introduction of 1,1′-diphenyl-substituted ferrocene (DPFc) and a large conjugated spacer of benzo[1,2-b:4,5-b′]dithiophene (BDT). UV-vis spectroscopy confirmed the increased main-chain conjugation and the improved coplanar backbone of this new-made organometallic polymer. XRD and GIWAXS measurement showed the regioregularity aggregation and a preferential face-on orientation of P(DTPDI-BDT-DPFc) backbone relative to the substrate. The following P(DTPDI-BDT-DPFc) devices indeed exhibit a specific, stable, and rewritable multilevel memory performance induced by the successive oxidation of BDT and Fc units. This work provides a reliable strategy for rationally introducing desirable functional spacers to realize excellent optoelectronic performance.