Nano- and micro-sized honeycomb patterns through hierarchical self-assembly of metal-loaded diblock copolymer vesicles

Herein we present a novel approach for fabricating metallic micro- and nano-structures in thin films via spin-coating solutions of diblock copolymer vesicles. A simple concept was developed, which is based on the metallization and self-assembly diblock copolymers. Firstly, vesicles incorporating the inorganic components are generated in solution by adjusting the solvent ratio in water-toluene mixtures. Subsequently, thin films are deposited onto a solid substrate via spin-coating. As a result micro- and nano-sized honeycomb structures are obtained; the pore diameter is dependent on the size and size distribution of the vesicles. Hence, control over the pattern dimensions and the degree of order can be achieved by tuning the vesicle diameter prior to film deposition. Finally, the block copolymer is extracted by means of oxygen plasma etching, leaving behind inorganic Au-nanostructures that mimic the original film morphology. The surface properties of these honeycomb patterns, in terms of hydrophobicity, can be adjusted by controlling the film thickness and the characteristic dimension of the pattern.