Abstract Graphite flake (average lateral size of 292 μm and average thickness of 13 μm)/copper composites with high volume fractions (72.08%-93.34 %) of graphite flake were produced by a vacuum hot pressing method. Results show that the composites are anisotropic due to the alignment of the surface plane of graphite flake perpendicular to the pressing direction. With increasing the volume fraction of graphite flake, the density of the composites decreases from 4.07 to 2.63 g cm−3, the relative density decreases apparently when the volume fraction of graphite flake are more than 82.6%, the in-plane electrical conductivity decreases from 14.71% to 2.45% of the international annealed copper standard, the in-plane coefficient of thermal expansion decreases from 6.6 to 2.2×10−6 /K, the in-plane bending strength decreases from 42.48 to 14.63 MPa, the in-plane compressive strength decreases 45.75 to 20.46 MPa while the in-plane thermal conductivity exhibits a maximum of 663.73 W m−1 K−1 at the volume fraction of GF 82.6%. The maximum in-plane thermal conductivity is caused by inter-flake pores that are not fully infiltrated by Cu. The in-plane and out-of-plane thermal conductivity agree well with the modified layers-in-parallel model and modified layers-in-series, respectively.

Natural graphite scarcity and conventional catalyst-induced defects limit the scalable production of high-performance coal-derived graphite. Herein, we demonstrate boric acid (H3BO3) as a green catalyst for coal graphitization by comparing with Fe2(SO4)3, FeCl3, FeS2, and H3BO3+FeCl3, with a focus on crystallite structure, 2H/3R polytypic graphite, and electrical conductivity. X-ray diffraction (XRD) analysis reveals that H3BO3 catalysis significantly elevates structural order, presenting a narrow and sharp (002) band, and increasing in-plane crystallite size (La), stacking height (Lc), and th

hundreds of graphene layers build up, they are called graphite. In technical terms, graphene is a carbon allotrope consisting of a single layer of atoms arranged Graphene () is a variety of the element carbon which occurs naturally in small amounts. In graphene, the carbon forms a sheet of interlocked atoms as hexagons one carbon atom thick. The result resembles the face of a honeycomb. When many hundreds of graphene layers build up, they are called graphite. In technical terms, graphene is a carbon allotrope consisting of a single layer of atoms arranged Graphene () is a variety of the element carbon which occurs naturally in small amounts. In graphene, the carbon forms a sheet of interlocked atoms as hexagons one carbon atom thick. The result resembles the face of a honeycomb. When many hundreds of graphene layers build up, they are called graphite. In technical terms, graphene is a carbon allotrope consisting of a single layer of atoms arranged in a honeycomb planar nanostructure. The name "graphene" is derived from "graphite" and the suffix -ene, indicating the presence of double bonds within the carbon structure. Graphene is known for its exceptionally high tensile strength, electrical conductivity, transparency, and being the thinnest two-dimensional material in the world. Despite the nearly transparent nature of a single graphene sheet, graphite (formed from stacked layers of graphene) appears black because it absorbs all visible light wavelengths. On a microscopic scale, graphene is the strongest material ever measured.