Disclose atomic interaction at the interface betweenpolyethylene and the edge ofmonolayer two-dimensional materials

Here we combine an advance synthesis of two-dimensional (2D) materials (MoSe₂) having well-defined atomic edge configurations and with ab-initio and atomistic molecular dynamics (MD) simulations to elucidate how atomic edges interact with polyethylene (HDPE) chains in a dilute solution assembly process. Our results reveal that Mo-terminated zigzag (Mo-ZZ) edges act as preferred nucleation sites and strongly interact with HDPE chains. The HDPE chains align in parallel with the Mo-ZZ edges and form arrays of lamellae that are perpendicular to the edges. Interestingly, atomic edge configurations are observed to dramatically change such interactions. The ab-initio calculation and MD simulation suggest that Se-terminated edges have lower binding energy with HDPE chains in comparison to other edges and that they are not expected to be preferred nucleation and lamellae growth sites. The crystallization discrepancy at different edges was demonstrated on the same piece of MoSe₂ with different types of edges. Following the Mo-ZZ edge preferred nucleation principle, controlled long-range alignment of HDPE lamellae can be realized by creating multilayer MoSe₂ with parallel atomic steps.