Photomagnetic hybrid ultrathin films

Two novel types of photomagnetic hybrid ultrathin film (film A and B) of metal cyanides have been fabricated by means of the modified Langmuir–Blodgett method using a smectite clay mineral. Film A is composed of an amphiphilic azobenzene cation, a montmorillonite, and Prussian Blue in which photocontrol in the magnetization was realized by the photoisomerization of azobenzene chromophore. The observed photomagnetic efficiency was large (ca. 11%) due to the well-organized structure of the ultrathin film. Film B is composed of a quaternary ammonium salt, a montmorillonite, and Co–Fe Prussian Blue in which the photoinduced magnetization caused by the electron transfer exhibited an anisotropic response with regards to the direction of the applied magnetic field. This phenomenon is ascribed to the unique structure of Co–Fe Prussian Blue formed onto the clay layer. Contribution to special issue “Magnetic field effects in Electrochemistry”