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The large-scale assembly of asymmetric colloidal particles is used in creating high-performance fibres. A similar concept is extended to the manufacturing of thin films of self-assembled two-dimensional crystal-type materials with enhanced and tunable properties. Here we present a spray-coating method to manufacture thin, flexible and transparent epoxy films containing zirconium phosphate nanoplatelets self-assembled into a lamellar arrangement aligned parallel to the substrate. The self-assembled mesophase of zirconium phosphate nanoplatelets is stabilized by epoxy pre-polymer and exhibits rheology favourable towards large-scale manufacturing. The thermally cured film forms a mechanically robust coating and shows excellent gas barrier properties at both low-and high humidity levels as a result of the highly aligned and overlapping arrangement of nanoplatelets. This work shows that the large-scale ordering of high aspect ratio nanoplatelets is easier to achieve than previously thought and may have implications in the technological applications for similar materials.

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ZnO nano-rods were grown on polycrystalline Zn foil by cathodic electrodeposition in an aqueous zinc chloride/calcium chloride solution at 80 • C. Variations in the solution concentration and substrate surface preparation were explored to shed light on the nucleation of the nano-rods. It was found that the nano-rod diameter increased with increasing solution concentration. Rolling striations and native ZnO on the surface of the Zn appeared to enhance nucleation and allowed more highly aligned, dense structures to be grown. By using low solution concentrations (5.0 × 10 −4 M ZnCl 2 ) and non-electropolished Zn substrates, well faceted, hexagonal nano-rod structures of dimension ∼80 nm diameter and >1 µm length were obtained. X-ray studies showed the samples to be highly aligned but containing a Zn-oxychloride impurity phase. Annealing caused the impurity phase to disappear and resulted in the films having a sharp photoluminescence double peak at 380/396 nm.