Molecular Self-Assembly in a Poorly Screened Environment: F4TCNQ on Graphene/BN
(a) Chemical structure of F4TCNQ molecule. (b) STM and (c) nc-AFM images of a 2D F4TCNQ island on graphene/BN. Image resolves individual chemical bonds within the F4TCNQ molecules and shows that molecules within the island lie flat on the surface in a close-packed rectangular lattice.
Charged molecules that would normally repel one another have been observed to attract each other on graphene due to a novel self-assembly mechanism
Significance and Impact
A new self-assembly mechanism should apply to other charged molecular systems involving 2D materials and provides a new route to engineer useful nanostructures
- Charged F4TCNQ molecules were observed to form tightly packed molecular islands on graphene supported by boron nitride.
- Atomic force microscopy was used to investigate the atomic-scale structure of 2D molecular islands on graphene.
- Molecular island formation was explained by a novel self-assembly mechanism for charged molecules in a poorly screened environ- ment where nanoscale work function heterogeneity exists.