Control of the lateral size and interparticle distance of niobate nanosheet colloid

Yamaguchi, Daisuke; Miyamoto, Nobuyoshi*; Koizumi, Satoshi; Nakato, Teruyuki*; Hashimoto, Takeji

The structure of niobate nanosheet in aqueous colloidal suspension was investigated by small-angle neutron scattering. The nanosheet, obtained by the exfoliation of layered KNbO single crystal, has a regular thickness of 1.8nm, while its lateral size (L) is variable from 100nm to several m depending on the preparation process. The influence of L on the structure of the colloidal suspensions was examined in this study and following two results were elucidated. (1) when L was larger than 1m, the orientational order of nanosheet particles was prior to those of positional order, while (2) when L was smaller than 1m, the positional order of nanosheet particles was prior to those of orientational order. This is an intriguing example showing the fact that the structure of constituent nanosheet particles control the liquid crystalline nature of the colloidal suspensions.