Two-dimensional array of polyoxomolybdate nanoball constructed by Langmuir-Blodgett semiamphiphilic method

A two-dimensional array of polyoxomolybdate nanoball ([(Mo72Mo60O372)-Mo-VI-O-V(CH3COO)(30)(H2O)(72)](42-), Mo-132) was successfully constructed by a Langmuir - Blodgett (LB) semiamphiphilic method by using Mo-132 aqueous solution as a subphase and dimethyldioctadecylammonium (DODA) as a cationic amphiphile. Conservation of molecular structure of the Mo-132 nanoball in the built-up LB film was confirmed by ultraviolet - visible (UV - vis) and infrared (IR) spectroscopy. Specular X-ray reflectivity (SXR) measurements combined with UV - vis spectroscopy revealed that the Mo-132/DODA LB film had a well-defined layered structure containing a densely packed two-dimensional array of the Mo-132 nanoballs. The electrochemical characteristics of the Mo-132 nanoballs were retained after the deposition onto the solid substrates, which verifies that the LB semiamphiphilic method is an effective way to fabricate thin films composed of functional nanosized clusters toward a two-dimensional molecular device.