Two-dimensional Dirac half-metallic Cr 2 C sheets with a clean surface and high stability (opens in new tab)

Two-dimensional (2D) chromium carbide (Cr2C) has attracted attention due to its predicted spin-dependent electronic structure and topological properties. Despite the successful synthesis of numerous MXenes, a family of 2D transition-metal carbides and nitrides, experimental isolation of 2D Cr2C sheets has remained elusive. Here we demonstrate that Cr2C sheets can be obtained from Cr2AlC by selectively extracting the Al layer using aqueous phosphoric acid followed by liquid-phase delamination....