Coalescence process of gold/silver core-shell nanoparticles located on carbon nanotube and graphene surfaces

The coalescence process at the initial stages has been investigated for the icosahedral and cuboctahedral Ag@Au clusters with 55 and 147 atoms supported on graphene and CNT surfaces. We have examined the different thermodynamics, dynamical, and structural properties of the supported clusters during the coalescence. Our results showed that the coalescence process makes the smaller cluster more stable than the bigger cluster and the smaller cluster experiences more coalescence than the bigger one. Also, the coalescence makes the cuboctahedral nanocluster more stable than the icosahedral cluster at the initial steps. The self-diffusion change is more significant for the icosahedral clusters than the cuboctahedral clusters at the initial steps. This result is in agreement with the total energy values and is due to the more tendency of the icosahedral structures to coalesce to be more stable than the cuboctahedral morphologies.