Solution Processable Iridescent Self-Assembled Nanoplatelets with Finely Tunable Interlayer Distances Using Charge- and Sterically Stabilizing Oligomeric Polyoxyalkyleneamine Surfactants

Photonic structures that are processable in organic solvents are critical to large-scale fabrication of device components. To provide a viable alternative to traditional lithographic methods, solution processable photonic structures are required to demonstrate fine control over critical device dimensions in the fabrication process. Photonic structures typically require long-range electrostatic forces that are effective only in aqueous solutions. Here we report a novel strategy of using oligomeric polyoxyalkyleneamine surfactants to prepare charge- and sterically stabilized nanoplatelets that can self-assemble into lamellar phases in nonaqueous solutions with finely tunable large interlamellar distances that can exceed 100 nm. Brilliant iridescence in the visible spectrum with tunable colors is demonstrated. The nanoplatelets are shown to circumvent the typical phase transition behavior from isotropic to nematic to columnar phase and transitioned into smectic phase at concentrations of phi < 0.01.