posted on 2024-01-04, 18:13authored byQi Zhou, Yuting Du, Liya Zhang, Ding Yi
Moiré superlattices formed
by graphene-covered
Ru(0001)
are known as excellent templates for the synthesis of monodispersed
transition metal nanoclusters, but an accurate description of the
structural evolution at the atomic level is still lacking. Herein,
using first-principles calculations, we systematically explore the
nucleation and growth of Pt nanoclusters (PtNCs) on such moiré
superlattices. Our calculations reveal that, for the nucleation of
PtNCs, FCC regions of the moiré superlattices are preferred
compared with other regions due to the stronger C-sp3 hybridization.
Considering different shapes and stacking modes, monolayer PtNCs of
regular hexagons and truncated triangles with three atoms removed
from each corner and bilayer PtNCs of partially covered second layers
with AA stacking are relatively stable. Comparing these stable configurations,
we can find out that PtNC with 27 atoms is the critical size where
the 2D growth mode will change to the 3D growth mode because of the
weakening of Pt–C bonds caused by the inhibition of C-sp3 hybridization. Our findings are of significance in revealing
the structural evolution of metal nanoclusters on graphene moiré
superlattices and other 2D templates.