Preparation And Properties Of Resistive Memory Based On Polyaniline/Oxidation Graphite Composites

The rapid developments of information put forward higher requirements on the information storage and logic circuit.Traditional silicon-based memory has been unable to meet the needs of modern use due to low storage density,high processing cost,complex device preparation process and material limitations.However,compared with the silicon-based memory,polymer material memory has many advantages,such as,easy processing of materials,lower processing power consumption,good material flexibility,large area production,fast response,high density storage;On the other hand,the graphene storage material memory device has good mechanical flexibility,fast response speed,high switching ratio,high density three-dimensional stack storage capacity characteristics,and it can realize miniaturization circuit.Therefore,based on organic polymer/graphene composite resistive memory devices are expected to have the advantages of both,to further improve the overall performance of organic memory devices.In this paper,sulfonated polyaniline-graphene oxide composites and polyaniline-graphene oxide composites were prepared by different composite methods.The composite materials were used as the active layers to prepare the sandwich memory devices.The electrical and mechanical properties of the composite devices were characterized and analyzed.The main work of this topic are as follows:(1)A mixed aqueous dispersion of sulfonated polyaniline(SPANI)with graphene oxide(GO)was prepared by simple physical doping,and spin-coated it on washed indium tin oxide glass(ITO)as an active layer,and Al was deposited as the electrode to make a sandwich structure Al/SPANI-GO/ITO device.At room temperature,the device had a nonvolatile storage performance by a current-voltage(I-V)test.It was found that the thickness of the active layer,the content ratio of GO and SPANI in the composite materials and the SPANI sulfonation time had an effect on the device storage performance.When the thickness of the active layer was 60 nm,the GO content in the composites was 10% and the SPANI sulfonation time was 3 h,the performances of the device were better.The ratio of current switch of the device was up to 104,the SET voltage was(-2.1)V.In the atmosphere,the device has good stability,lasting memory duration and fast response speed.Finally,through thetheoretical simulation of the I-V curve,it was inferred that the storage mechanism was related to the charge transfer between GO and SPANI molecules.(2)The GO/polyaniline(PANI)composites were prepared by in situ polymerization of aniline on GO with ammonium persulfate(APS)as oxidant.Al/GO-PANI/ITO memory devices were prepared by spin-coating the N-methyl pyrrolidone(NMP)solution of GO-PANI on the cleaned indium tin oxide glass(ITO)as the active layer and the electrode electrodeposited with Al.At room temperature,the device had a nonvolatile storage performance by a current-voltage(I-V)test.It was found that the PANI polymerization time,the thickness of the active layer and the content ratio of GO and SPANI in the composite materials could effect the storage performance of the device.It was found that when the PANI polymerization time was long,so that the surface roughness of the film could further affect the stability of the performance.When the thickness of the active layer was 80 nm and the GO content in GO-PANI composites was 8 wt%,the ratio of current switch of the device was 8×103,SET voltage was(-1.8)V.Finally,through the theoretical simulation of the I-V curve,it was inferred that the storage mechanism was related to the charge transfer between GO and SPANI molecules.