Scattering analysis for highly oriented colloidal dispersion consisting of sheet-like inorganic particles

Yamaguchi, Daisuke; Miyamoto, Nobuyoshi*; Nakato, Teruyuki*; Koizumi, Satoshi*; Ota, Noboru*; Yagi, Naoto*; Hashimoto, Takeji; Kawakatsu, Toshihiro

Self-assembled structures of aqueous colloidal dispersions of niobate nanosheets having a uniform thickness of d = 1.6 nm and an average lateral dimension of L = 650 nm, hence an extremely large nominal aspect ratio (L/d) of 400 were studied by micro-beam synchrotron small-angle X-ray scattering (SAXS). The results elucidated highly orientated, periodic layered liquid crystalline phase exhibiting a multiple-order scattering peaks. The line-profiles of the multiple-order peaks were analyzed in the directions both parallel and perpendicular to the one-dimensional stacks of the nanosheets for each order of the peaks. The results were compared with the formula based on harmonic approximation. An experimental problem associated with effects of orientation distributions of the stacks on the line profile analyses was quantitatively examined.