Preparation of Wrinkled Nanoribbons Consisting of Langmuir-Blodgett Films

Langmuir-Blodgett films are normally deposited on hard substrates, such as mica plates. In this study, soft substrates consisting of a poly(dimethylsiloxane) elastomer were used for film deposition. A docosanoic acid monolayer was transferred onto the substrate by moving it in an upward direction while immersed in a subphase CoCl2 solution. Interestingly, the obtained deposited layer showed a ribbon-like morphology that oriented itself parallel to the water surface. Subsequently, by shrinking the substrate, wrinkled ribbons were obtained. This novel wrinkling method is unique to soft substrates because hard substrates cannot be shrunk. Such a wrinkling method can be useful to control the morphology of the LB films, and thus improve its properties as functional materials.