▎ 摘　　要

We present an industrially relevant, single-step, chemicaland solvent-free, thermomechanical exfoliation (TME) process to produce graphene nanoplatelet (GNP) flakes, comprising mixtures of few- and multilayered graphene (FLG and MLG, respectively), starting from flake graphite. The specific energy required to produce GNP flakes with specific surface area (SSA) as high as 430 m(2)/g and aspect ratio as high as 250 is between 36 and 61 kJ/g. The evolution of the material is tracked throughout the process to elucidate the mechanism of graphite delamination. Bulk characterization methods, including thermogravimetric analysis, Raman spectroscopy, X-ray diffraction, and Brunauer-Emmett- Teller (BET) physisorption analysis, are used to monitor the changes in SSA, combustion temperature, relative composition, and to assess the extent of exfoliation. The process can be used to delaminate a range of graphitic materials, including fine (-325 mesh) and coarse (+50 mesh) graphite flakes, and expanded graphite to produce flake-shaped GNPs, suitable for various functional applications, including conductive polymer composites and coatings, supercapacitors, batteries, lubricants, and sensors.