Studies of liquid crystalline self-assembly of GdF₃ nanoplates by in-plane, out-of-plane SAXS

Directed self-assembly of colloidal nanocrystals into ordered superlattices enables the preparation of novel metamaterials with diverse functionalities. Structural control and precise characterization of these superlattices allow the interactions between individual nanocrystal building blocks and the origin of their collective properties to be understood. Here, we report the directed liquid interfacial assembly of gadolinium trifluoride (GdF₃) nanoplates into liquid crystalline assemblies displaying long-range orientational and positional order. The macroscopic orientation of superlattices is controlled by changing the subphases upon which liquid interfacial assembly occurs. The assembled structures are characterized by a combination of transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) measurements performed on a laboratory diffractometer. By doping GdF₃ nanoplates with europium (Eu³⁺), luminescent phosphorescent superlattices with controlled structure are produced and enable detailed structural and optical characterization.