Large-scale production of low-cost, highly-stable, metal-free two-dimensional (2D) crystals now become an important challenge for many applications including energy conversion and storage. Here, we demonstrate an efficient and eco-friendly method for the scalable synthesis of 2D crystals and their applications for energy conversion and storage. The first approach involves edge-selective functionalization of graphite into graphene nanoplatelets (GnPs) by a simple mechanochemical ball-milling process . The approach is an important step toward high-yield exfoliation of three-dimensional graphite into two-dimensional crystals with minimal basal plane distortion. The second approach is scalable synthesis of 2D crystals with periodic holes and heteroatoms via polycondensation between A3 and B- monomers. The resultant 2D crystals displayed outstanding electrochemical performance . Our findings suggest that the 2D crystals can be simply prepared and conveniently used as base materials for a wide range of applications from wet chemistry to device applications .
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