An ITO/TPAPAM‐GO/Al memory device (see figure; ITO = indium tin oxide, TPAPAM‐GO = graphene oxide covalently grafted with triphenylamine‐based polyazomethine) exhibits typical bistable electrical switching and a nonvolatile rewritable memory effect with a turn‐on voltage of −1.0 V and an ON/OFF‐state current ratio of more than 103. Both ON and OFF state are stable under a constant voltage stress and survive up to 108 read cycles at a read voltage of −1.0 V.

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As the thinnest material ever known in the universe, graphene has been attracting tremendous amount of attention in both materials science and condensed-matter physics since its successful isolation a few years ago. This one-atom-thick two-dimensional pseudo-infinite nano-crystal consists of sp(2)-hybridized aromatic carbon atoms covalently packed into a continuous hexagonal lattice. Graphene exhibits a range of unique properties, viz., high three-dimensional aspect ratio and large specific surface area, superior mechanical stiffness and flexibility, remarkable optical transmittance, extraordinary thermal response and excellent electronic transport properties, promising its applications in the next generation electronics. To switch graphene and its derivatives between ON and OFF states in nanoelectronic memory devices, various techniques have been developed to manipulate the carbon atomic sheets via introducing the valence-conduction bandgap and to enhance their processability. In this article, we review the utilization of electrically, thermally and chemically modified graphene and its polymer-functionalized derivatives for switching and information storage applications. The challenges posed on the development of novel graphene materials and further enhancements of the device switching performance have also been discussed.

Viologen-inspired aromatic molecules, polymers, and functional materials and their versatile applications will be introduced in this review.

Electrical properties and non-volatile memory effect of the [Fe(HB(pz)3)2] spin crossover complex integrated in a microelectrode device Appl. Phys. Lett. 99, 053307 (2011); 10.1063/1.3616147 Observation of bistable resistance memory switching in CuO thin films Appl. Phys. Lett. 94, 102107 (2009); 10.1063/1.3098071Bistable electrical switching and write-once read-many-times memory effect in a donor-acceptor containing polyfluorene derivative and its carbon nanotube composites

Major disadvantages of black phosphorus (BP) are its poor air-stability and poor solubility in common organic solvents. The best way to solve this problem is to incorporate BP into a polymer backbone or a polymer matrix to form novel functional materials that can provide both challenges and opportunities for new innovation in optoelectronic and photonic applications. As a proof-of concept application, we synthesized in situ the first highly soluble conjugated polymer-covalently functionalized BP derivative (PDDF-g-BP) which was used to fabricate a resistive random access memory (RRAM) device with a configuration of Au/PDDF-g-BP/ITO. In contrast to PDDF without memory effect, PDDF-g-BP-based device exhibits a nonvolatile rewritable memory performance, with a turn-on and turn-off voltages of +1.95 V and -2.34 V, and an ON/OFF current ratio of 10 . The current through the device in both the ON and OFF states is still kept unchanged even at 200th switching cycle. The PDDF/BP blends show a very unstable memory performance with a very small ON/OFF current ratio.

A nanoaggregated dispersed red 1‐grafted poly(N‐vinylcarbazole) (abbreviated PVDR) is self‐assembled via π–π stacking interactions of the carbazole groups in the polymer system after adding a solution of PVDR in N,N‐dimethylformamide to dichloromethane. Upon self‐assembly, the nanoaggregated PVDR film displays helical columnar stacks with large grain sizes, whereas a non‐aggregated PVDR film exhibits an amorphous morphology with smaller grain size. A write‐once read‐many‐times (WORM) memory device is shown whereby a pre‐assembled solution of PVDR is spin‐coated as the active layer and is sandwiched between an aluminum electrode and an indium‐tin‐oxide (ITO) electrode. This device shows very good memory performance, with an ON/OFF current ratio of more than 105 and a low misreading rate through the precise control of the ON and OFF states. The stability of the nanoaggregated PVDR device is much higher than that of the non‐nanoaggregated PVDR device. This difference in device stability under constant voltage stress can be mainly attributed to the difference in the film crystallinity and surface morphology. No degradation in current density was observed for the ON‐ and OFF‐states after more than one hundred million (108) continuous read cycles indicating that both states were insensitive to the read cycles. These results render the nanoaggregated PVDR polymer as promising components for high‐performance polymer memory devices.

Memristors with enormous storage capacity and superior processing efficiency are of critical importance to overcome the Moore’s Law limitation and von Neumann bottleneck problems in the big data and artificial intelligence era. In particular, the integration of multifunctionalities into a single memristor promises an essential strategy of obtaining a high-performance electronic device that satisfies the nowadays increasing demands of data storage and processing. In this contribution, we report a proof-of-concept polymer memristive processing-memory unit that demonstrates programmable information storage and processing capabilities. By introducing redox active moieties of triphenylamine and ferrocene onto the pendants of fluorene skeletons, the conjugated polymer exhibits triple oxidation behavior and interesting memristive switching characteristics. Associated with the unique electrochemical and electrical behavior, the polymer device is capable of executing multilevel memory, decimal arithmetic operations of addition, subtraction, multiplication and division, as well as simple Boolean logic operations.