The excess of surface dangling bonds makes the formation of free-standing two-dimensional (2D metals unstable and hence difficult to achieve. To date, only a few reports have demonstrated
2D metal formation over substrates. Here, we show a free-standing crystalline single-atom-thick
layer of iron (Fe) using in situ low-voltage aberration-corrected transmission electron microscopy
and supporting image simulations. First-principles calculations confirm enhanced magnetic
properties for single-atom-thick 2D Fe membranes. This work could pave the way for new
2D structures to be formed in graphene membranes.

这工作不错呀，与石墨烯不同，Fe本身就具有磁性的。