Preparation of azobenzene-mica complex and its photoresponse to ultraviolet irradiation

A novel vapor phase intercalation method was applied to the preparation of complexes of azobenzene and synthetic tetra-silicic mica in order to obtain photoresponsive solids. Photoresponse was monitored by measuring the basal spacing, d(001). The basal spacing of the complex obtained was found to decrease by 4% after 1 h of ultraviolet (UV) irradiation (λ = 365 nm). The initial basal spacing was recovered after storage for 2 days at room temperature and following 1 h of heat treatment at 50°C. Such a reversible basal spacing change was observed after more than 15 successive cycles. The photoresponsive change was attributed to the isomerization of incorporated azobenzene molecules.