Molecular assembly of fullerene-conjugated phthalocyanine derivative on Au(111) at single molecular level

Molecular adlayers of doubly C60-conjugated phthalocyanine derivatives ((C60)2NiPc) were examined on bare and zinc(II) octaethylporphyrin (ZnOEP)- and coronene-modified Au(111) surfaces. Electrochemical scanning tunneling microscopy (EC-STM) has revealed the structure of the (C60)2NiPc adlayer at single molecular level. The (C60)2NiPc adlayer is strongly influenced by the underlying organic layers, i.e., a disordered, a packed structure of (C60)2NiPc was found on a clean Au(111) surface because of the strong interaction between (C60)2NiPc molecule and Au(111) substrate, whereas a single (C60)2NiPc molecule was clearly distinguished both on ZnOEP and coronene adlayers at a low coverage of (C60)2NiPc molecules. The obtained results in the present study suggest that the underlying organic adlayers play an important role in the formation process of the (C60)2NiPc molecule adlayer.

Graphical abstractThe molecular adlayer of fullerene–phthalocyanine hybrid compound, doubly C60-conjugated phthalocyanine derivative ((C60)2NiPc) was formed on bare and zinc octaethylporphyrin-modified Au(111). The structure of the (C60)2NiPc adlayer was found to depend on the underlying organic layer. Individual (C60)2NiPc molecules were clearly imaged by high-resolution STM images at single molecular level.Figure optionsDownload full-size imageDownload as PowerPoint slide