The collection of 2D materials is gradually expanding. At the moment the database contains 6025 materials, of which There are Number of materials by bandgap: Naturally, only a fraction of these materials are stable by themselves, but freestanding stability was not the main focus of this work, since materials can be stabilized by other means such as a substrate.

For the top-down materials exfoliated from stable layered materials, exfoliation energy is equal to E_above_hull which is an indication of stability. Number of top-down materials by exfoliation energy per atom:

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