Park, Jinseo Shim, Jae ho Son, Dong Ick 2025-11-06T09:02:06Z 2025-11-06T09:02:06Z 2025-10-30 2025-04 https://pubs.kist.re.kr/handle/201004/153414 Nonvolatile hybrid inorganic/organic bistable memory devices fabricated utilizing Co3O4-graphene core-shell quantum dots (QDs) embedded in an insulating poly (methyl methacrylate) (PMMA) polymer matrix as active layer which were fabricated using a spin-coating technique. To improve the quantum confinement of Co3O4 QD, graphene, which has high electron affinity, was synthesized with Co3O4 QD core as a shell to form a core-shell structure that serves as an excellent trap site. Transmission electron microscopy (TEM) images revealed that Co3O4-graphene core-shell QDs with a diameter of approximately 5 nm were formed among the PMMA polymer matrix. Current-voltage (I-V) measurements on Al/ Co3O4-graphene core-shell QDs embedded in PMMA polymer matrix/indium-tin-oxide (ITO) devices at 300 K showed electrical bistability. The maximum ON/OFF ratio of the current bistability for the OBMDs was as large as 1.8 × 104, the cycling endurance for the devices was above 2.5 × 103 cycles, and retention times for the devices were larger than 5.8 × 104 s. The carrier transport mechanisms for the devices were described by fitting the experimental I-V data using several models. English Elsevier Co3O4-graphene core-shell QDs-PMMA insulating polymer composites structured nonvolatile bistable memory devices Article 10.1016/j.cartre.2025.100473 1 Carbon Trends, v.19 Carbon Trends 19 Y scopus