Abstract:
A composite structure disclosed includes a base (X) and a layer (Y) stacked on the base (X). The layer (Y) includes a reaction product (R). The reaction product (R) is a reaction product formed by a reaction at least between a metal oxide (A) and a phosphorus compound (B). A peak for a binding energy of an oxygen-atom 1s orbital observed by X-ray photoelectron spectroscopy of the layer (Y) is located at 532.0 eV or higher, and the peak has a half width of less than 2.0 eV.
Abstract:
The method disclosed includes: a step (I) of preparing a dispersion liquid (S) including an aluminum compound (A); a step (II) of mixing the dispersion liquid (S) and a predetermined phosphorus compound (B) so as to prepare a coating liquid (U); a step (III) of applying the coating liquid (U) onto the base (X) so as to form a precursor layer of the layer (Y); and a step (IV) of subjecting the precursor layer to heat treatment at a temperature of 110° C. or more so as to form the layer (Y). The aluminum compound (A) can be formed by adding an acid to a solution including an aluminate. The number of moles (NM) of aluminum atoms derived from the aluminum compound (A) and the number of moles (NP) of phosphorus atoms derived from the phosphorus compound (B) satisfy 0.8≦(NM)/(NP)≦4.5.