Photomechanical response of azobenzene/organophilic mica complexes

To clarify whether photomechanical response is limited to the special combination of azobenzene (AzBz)/organophilic tetrasilicic mica (TSM) complexes, another swelling synthetic fluoro-mica, lithium taeniolite, was used as a starting host for AzBz/organophilic mica complexes. Basal spacings of organophilic taeniolites (o-TNs) prepared by the intercalation of trimethylalkylammonium (TMAA) into the TN increased linearly as alkyl chain length in TMAA increased from 2.44 to 2.86 nm. This indicates paraffin-type arrangement of TMAA in the TN gallery. Intercalation of AzBz to o-TN was performed via the gas phase at 100 °C. Photoresponses of AzBz/o-TN complexes were examined by XRD measurement under alternate UV and visible light irradiation. A decrease in basal spacing was observed under UV irradiation, and an increase was under visible light irradiation. Basal spacing change was 0.09–0.18 nm, which corresponds to 3–5% of the AzBz/o-TN basal spacing. These results indicate that reversible photomechanical response is a general phenomenon for AzBz/organophilic mica complexes.