Self-Assembled Peptide Nano-Materials for Optic and Electronic Applications

In recent years, a key direction in the field of electronics and electro-optics involves the transition from inorganic to organic components, thus paving the way towards flexible and wearable electronic and light emitting devices. Bio-inspired organic materials may be the next-generation of organic optoelectronic devices based on self-organization principles, which allow facile synthesis, eco-friendliness, resistance to oxidation and no need for heavy metal doping.

Recent advances in bioorganic nanotechnology have established the notion that very simple building blocks, such as dipeptides, can form regular nanostructures with distinct mechanical, optical, piezoelectric and electronic properties. In particular, members of the diphenylalanine (FF) peptide archetypical family have been shown to form various morphologies and ordered nanostructures such as tubes, rods, fibrils, spheres, plates and macroscopic hydrogels with nano-scale order.

Several studies have explored the piezoelectric properties of the diphenylalanine (FF) peptide. In the presence of an external electric field, vertically aligned FF microrod arrays can be organized on a substrate, resulting in enhanced piezoelectric response.

Here we show the ability of FF and other similar peptide assemblies to be used in various electronics and optics application as new bioorganic materials. FF assemblies can act as an active optical waveguiding material, allowing locally excited states to propagate along the axis of the assemblies. In addition, Fmoc capped building blocks exhibit remarkable optical properties, such as quantum confinement and fluorescence. Other rod-like assemblies and toroid-like assemblies exhibit remarkable physicochemical features, including high thermal stability, metallic-like mechanical rigidity, luminescence, piezoelectricity and semi-conductivity.