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In recent years, microelectronics technology has developed at a rapid pace. The integration level, packaging density, and operating frequency of chips in handheld devices such as smartphones and tablets, as well as in devices like LEDs, have all increased significantly. The power-to-volume ratio has been rising, which leads to a rapid increase in the heat flux density within these chips. Excessively high chip temperatures can severely affect its operational efficiency, system stability, and the lifespan of the components, which has led to an urgent need for new, efficient cooling technologies or cooling materials. Graphene possesses extremely excellent thermal conductivity; the in-plane thermal conductivity of graphene sheets at room temperature can reach up to about 5300 W/mK. Graphene films are composed of stacked graphene sheets, and they also exhibit extremely excellent in-plane thermal conductivity; at room temperature, their thermal conductivity can reach up to about 1000 W/mK, which is far superior to that of traditional metal thermal conductors such as copper and aluminum. However, graphene films have a very low thermal conductivity because they rely solely on the weak van der Waals forces between the graphene layers in the thickness direction, which limits their use as efficient two-dimensional heat dissipation materials. To address this issue, the research team led by Professor Jiang Dazhi from the National University of Defense Technology proposed a three-dimensional hybrid thin film material composed of carbon nanorings, namely ultrashort carbon nanotubes, which bridge graphene sheets in the thickness direction. This structure significantly enhances the thermal conductivity of the graphene film in that direction, opening up new avenues for research on novel and efficient two-dimensional heat dissipation materials. The team first introduced the polymer carbon source polymethyl methacrylate (PMMA) and the metal catalyst precursor Ni(COOH)2 into the conventional graphene film method, inserting them between the layers of the graphene film to form a hybrid film ； The hybrid film is then subjected to high-temperature treatment; under the catalysis of metal Ni produced by pyrolysis at high temperatures, the carbon generated from the pyrolysis of the polymer carbon source grows tubular nanocarbon structures between the graphene layers. Due to the confinement effect of the graphene sheets, the length of these nanocarbon tubes is very short, and they are referred to as carbon nanorings. Together with the graphene sheets, these carbon nanorings form a three-dimensional hybrid film of carbon nanorings/graphene. Due to the interfacial bridging effect of carbon nanorings between graphene sheets, the thermal conductivity of this hybrid film in the thickness direction is about 3 times higher than that of conventional graphene films, reaching approximately 5.81 W/mK, while the in-plane thermal conductivity remains almost unchanged. This carbon nanorings/graphene three-dimensional hybrid film not only holds promise for use in the field of new, high-efficiency two-dimensional heat dissipation materials, but its unique all-carbon three-dimensional nanostructure also has the potential to find applications in areas such as electrode materials and supercapacitors.