Observation and Electrical Properties of Functionalized Dendrimer Monolayers by Using SPMs

We synthesized dendrimers containing light switchable units, azobenzene group. We also report the example of a dendrimer containing 48 azobenzene that is electrically conducting using STM. The dendrimer with azobenzene group compared trans form and cis form at electrical properties. By irradiation of 365 [nm] light, the trans state current of G4-48 Azo dendrimer was increased, which was originated by the photoisomerization process of the azobenzene group on the periphery from trans to cis form. All of the conductivities were ohmic, there is no evidence of polarization on switching the current direction, and the conductivity values remained constant for several hours. This demonstrates that the conductivity is electronic, not ionic. This suggests that optical behavior and conductivity change are affected by the functional group and symmetric chain.