Abstract: The present invention provides a layered double hydroxide with improved conductivity, a layered double hydroxide and a composite material containing the layered double hydroxide. The layered double hydroxide is represented by the general formula: [Mg2+(1-y)M1?+y]1-x[Al3+(1-z)M2?+z]x(OH)2An?x/n.mH2O, wherein 0.1?x?0.4, 0?y?0.95, and 0?z?0.95, provided that both y and z are not 0 at the same time; ?=1 or 2; ?=2 or 3; An? is an n-valent anion, provided that n is an integer of 1 or greater; m?0; M1?+ is a cation of at least one substituent element selected from monovalent elements, transition metal elements, and other elements with an ionic radius greater than that of Mg2+; and M2?+ is a cation of at least one element selected from divalent elements, transition metals, and other elements with an ionic radius greater than that of Al3+.

Abstract: Provided is a hydroxide-ion-conductive dense membrane having a He permeability per unit area of 10 cm/min·atm or less. The present invention provides a highly-densified hydroxide-ion-conductive membrane that can significantly reduce permeation of substances other than hydroxide ions (in particular, Zn, which may cause growth of dendritic zinc in a zinc secondary battery) and that is particularly suitable for use in, for example, a separator for a battery (in particular, a zinc secondary battery, which may cause growth of dendritic zinc).

Abstract: Provided is a hydroxide-ion-conductive dense membrane having a He permeability per unit area of 10 cm/min·atm or less. The present invention provides a highly-densified hydroxide-ion-conductive membrane that can significantly reduce permeation of substances other than hydroxide ions (in particular, Zn, which may cause growth of dendritic zinc in a zinc secondary battery) and that is particularly suitable for use in, for example, a separator for a battery (in particular, a zinc secondary battery, which may cause growth of dendritic zinc).

Abstract: The present invention provides a layered double hydroxide with improved conductivity, a layered double hydroxide and a composite material containing the layered double hydroxide. The layered double hydroxide is represented by the general formula: [Mg2+(1-y)M1?+y]1-x[Al3+(1-z)M2?+z]x(OH)2An?x/n.mH2O, wherein 0.1?x?0.4, 0?y?0.95, and 0?z?0.95, provided that both y and z are not 0 at the same time; ?=1 or 2; ?=2 or 3; An? is an n-valent anion, provided that n is an integer of 1 or greater; m?0; M1?+ is a cation of at least one substituent element selected from monovalent elements, transition metal elements, and other elements with an ionic radius greater than that of Mg2+; and M2?+ is a cation of at least one element selected from divalent elements, transition metals, and other elements with an ionic radius greater than that of Al3+.

Abstract: The present invention provides a layered double hydroxide with improved conductivity, a layered double hydroxide and a composite material containing the layered double hydroxide. The layered double hydroxide is represented by the general formula: [Mg2+(1-y)M1?+y]1-x[Al3+(1-z)M2?+z]x(OH)2An?x/n.mH2O, wherein 0.1?x?0.4, 0?y?0.95, and 0?z?0.95, provided that both y and z are not 0 at the same time; ?=1 or 2; ?=2 or 3; An? is an n-valent anion, provided that n is an integer of 1 or greater; m?0; M1?+ is a cation of at least one substituent element selected from monovalent elements, transition metal elements, and other elements with an ionic radius greater than that of Mg2+; and M2?+ is a cation of at least one element selected from divalent elements, transition metals, and other elements with an ionic radius greater than that of Al3+.

Abstract: Provided is a method of forming a layered double hydroxide (LDH) dense membrane on the surface of a porous substrate. The LDH dense membrane is composed of an LDH represented by the formula: M2+1-xM3+x(OH)2An?x/n·mH2O where M2+ represents a divalent cation. M3+ represents a trivalent cation, An? represents an n-valent anion, n is an integer of 1 or more, and x is 0.1 to 0.4. This method includes (a) providing a porous substrate, (b) evenly depositing, on the porous substrate, a nucleation material capable of providing a nucleus from which the crystal growth of the LDH starts; and (c) hydrothermally treating the porous substrate in an aqueous stock solution containing a constituent element of the LDH to form the LDH dense membrane on the surface of the porous substrate. The method of the present invention can form a highly-densified LDH membrane evenly on the surface of a porous substrate.

Abstract: Provided is a hydroxide-ion-conductive dense membrane having a He permeability per unit area of 10 cm/min·atm or less. The present invention provides a highly-densified hydroxide-ion-conductive membrane that can significantly reduce permeation of substances other than hydroxide ions (in particular, Zn, which may cause growth of dendritic zinc in a zinc secondary battery) and that is particularly suitable for use in, for example, a separator for a battery (in particular, a zinc secondary battery, which may cause growth of dendritic zinc).

Abstract: There is provided a silica membrane 1 formed on a porous substrate. A desorbed ionic strength of water having a temperature of 500° C. in a temperature-programmed desorption analysis of water of the silica membrane is 2,000,000/g. The silica membrane 1 is manufactured by allowing a silica sol having a water concentration of 0.03 to 3 mass % to adhere to a porous substrate by an ethanol solvent, drying the silica sol by sending air having a dew point of ?70 to 0° C., and firing the dried silica sol at 200 to 400° C.

Abstract: There is provided a silica membrane 1 formed on a porous substrate. A desorbed ionic strength of water having a temperature of 500° C. in a temperature-programmed desorption analysis of water of the silica membrane is 2,000,000/g. The silica membrane 1 is manufactured by allowing a silica sol having a water concentration of 0.03 to 3 mass % to adhere to a porous substrate by an ethanol solvent, drying the silica sol by sending air having a dew point of ?70 to 0° C., and firing the dried silica sol at 200 to 400° C.