TY - JOUR
T1 - Interaction between Iron and Graphene Nanocavity
T2 - Formation of Iron Membranes, Iron Clusters, or Iron Carbides
AU - Chen, Shuang
AU - Zeng, Xiao Cheng
N1 - Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/4/5
Y1 - 2017/4/5
N2 - Motivated from a recent experimental study on filling of a graphene nanocavity by iron membrane at room temperature (Science 2014, 343, 1228), we perform a comprehensive study of morphology changes of two-dimensional Fe membranes and iron carbides embedded in graphene nanocavities with specific sizes and shapes using the first-principles calculations and ab initio molecular dynamics simulations. Our simulations show that Fe atoms tend to gradually seal the graphene nanocavity via growing a metastable Fe membrane until the nanocavity is completely covered. Notably, a densely packed Fe membrane in the graphene nanocavity shows higher structural stability than a loosely packed one as long as more triangular lattices can form to release high tensile strain. The Fe membrane under high tensile strain tends to collapse and turns into a three-dimensional Fe cluster upon detaching from the edge. The structural transformation of Fe nanostructures follows the melting recrystallization mechanism at ambient temperatures in high vacuum. Moreover, the iron carbide can also exist in the graphene nanocavity and once formed can be highly stable even at 1200 K.
AB - Motivated from a recent experimental study on filling of a graphene nanocavity by iron membrane at room temperature (Science 2014, 343, 1228), we perform a comprehensive study of morphology changes of two-dimensional Fe membranes and iron carbides embedded in graphene nanocavities with specific sizes and shapes using the first-principles calculations and ab initio molecular dynamics simulations. Our simulations show that Fe atoms tend to gradually seal the graphene nanocavity via growing a metastable Fe membrane until the nanocavity is completely covered. Notably, a densely packed Fe membrane in the graphene nanocavity shows higher structural stability than a loosely packed one as long as more triangular lattices can form to release high tensile strain. The Fe membrane under high tensile strain tends to collapse and turns into a three-dimensional Fe cluster upon detaching from the edge. The structural transformation of Fe nanostructures follows the melting recrystallization mechanism at ambient temperatures in high vacuum. Moreover, the iron carbide can also exist in the graphene nanocavity and once formed can be highly stable even at 1200 K.
KW - ab initio molecular dynamics simulations
KW - graphene edges
KW - iron carbides
KW - two-dimensional Fe membranes/monolayers
KW - ultrafine Fe clusters
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U2 - 10.1021/acsami.7b00904
DO - 10.1021/acsami.7b00904
M3 - Article
C2 - 28290196
AN - SCOPUS:85017096624
SN - 1944-8244
VL - 9
SP - 12100
EP - 12108
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 13
ER -