Relation between mean lateral size and structure in the niobate nanosheet colloidal suspension

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

The structure of niobate nanosheets in aqueous colloidal suspensions was investigated by small-angle neutron scattering (SANS). The nanosheet, obtained by the exfoliation of layered KNbO single crystal, has a regular thickness (d) of 1.8 nm, while lateral size (L) is variable from 100 nm to 10 m depending on the preparation process. Such an large aspect (i.e., L/d) ratio is peculiar to the nanosheet of KNbO crystal, and has never been obtained by other type of clay nanosheet. According to the SANS measurement, the aspect ratio of the nanosheet is deeply related to the regularity of the spacing between the nanosheet particles in the colloidal suspension. A comprehensive comparison between niobate nanosheets and other clay nanosheets is argued.