Fig. 2: The simulated mechanism for the amorphization.

a The snapshots of the surface oxidation process. b The fraction of surface O in the total number of surface C and O. c The snapshots of the slices of O atoms penetration process. d The time-dependent total number of the O that bind with Cu, including the O on the surface and bulk. e The snapshots for the O departing process. f The results of the polyhedral template matching of the final structure. It is plotted by OVITO. For all the pictures, the red, yellow, and blue circle stand for Cu, O, and C, respectively.