Abstract: Provided is an air electrode/separator assembly including a hydroxide ion conductive separator including a hydroxide ion conductive solid electrolyte; and an air electrode layer having a thickness of 1,000 nm or smaller that is provided on one side of the hydroxide ion conductive separator and that includes a hydroxide ion conductive material, an electron conductive material, and an air electrode catalyst, provided that the hydroxide ion conductive material may be the same material as the hydroxide ion conductive solid electrolyte or the air electrode catalyst, and provided that the electron conductive material may be the same material as the air electrode catalyst.

Abstract: A layered double hydroxide is represented by the following formula (I): Ni2+1?(x+y+z)Fe3+xV3+yCo3+z(OH)2An?(x+y+z)/n·mH2O . . . (I). In one embodiment, in the formula (I), (x+y+z) is from 0.2 to 0.5, “x” represents more than 0 and 0.3 or less, “y” represents from 0.04 to 0.49, and “z” represents more than 0 and 0.2 or less.

Abstract: Provided is an air electrode/separator assembly including: a hydroxide ion conductive dense separator; an interface layer containing a hydroxide ion conductive material and an electron conductive material and covering one side of the hydroxide ion conductive dense separator; and an air electrode layer provided on the interface layer and including an outermost catalyst layer composed of a porous current collector and a layered double hydroxide (LDH) covering a surface thereof. The outermost catalyst layer has a porosity of 60% or more.

Abstract: Provided is an air electrode/separator assembly including a hydroxide ion conductive separator including an inner space, a pair of catalyst layers covering both surfaces of the hydroxide ion conductive separator and containing a catalyst for an air electrode, a hydroxide ion conductive material, and an electron conductive material, a pair of gas diffusion electrodes provided on the pair of catalyst layers on a side opposite to the hydroxide ion conductive separator, and a water absorption/desorption layer provided so as to contact both of the pair of catalyst layers, having water absorbability and desorbability. One of the pair of catalyst layers is a catalyst layer for discharge and the other of the pair of catalyst layers is a catalyst layer for charge; and the hydroxide ion conductive separator, the catalyst layer, and the gas diffusion electrode are arranged vertically, and the water absorption/desorption layer is positioned below the catalyst layer.

Abstract: Provided is an air electrode/separator assembly including: a hydroxide ion conductive separator, an interface layer containing a hydroxide ion conductive material and an electron conductive material and covering one side of the hydroxide ion conductive separator; an air electrode layer provided on the interface layer and including a catalyst layer composed of a porous current collector and a layered double hydroxide (LDH) covering a surface thereof, and a water repellent porous layer covering a surface of the air electrode opposite to the hydroxide ion conductive separator.

Abstract: Provided is an air electrode/separator assembly including a hydroxide ion conductive separator, a catalyst layer including a catalyst for an air electrode, a hydroxide ion conductive material, an electron conductive material, a binder, and a humidity conditioning material and covering one side of the hydroxide ion conductive separator, and a gas diffusion electrode provided on the catalyst layer on a side opposite to the hydroxide ion conductive separator.

Abstract: A layered double hydroxide is represented by the following formula (I): Ni2+1?(x+y+z)Fe3+xV3+yCo3+z(OH)2An?(x+y+z)/n·mH2O . . . (I). In one embodiment, in the formula (I), (x+y+z) is from 0.2 to 0.5, “x” represents more than 0 and 0.3 or less, “y” represents from 0.04 to 0.49, and “z” represents more than 0 and 0.2 or less.

Abstract: Provided is a negative electrode for use in a zinc secondary battery containing (A) ZnO particles and (B) at least two selected from the group consisting of (i) metallic Zn particles having an average particle size D50 of 5 to 80 ?m, (ii) at least one metal element selected from In and Bi, and (iii) a binder resin having a hydroxyl group.

Abstract: Provided is an air electrode/LDH separator assembly including: a rigid porous layer having rigidity and air permeability, wherein the rigidity is defined as a proportion of displacement in a compression direction of less than 3% when pressurized at 0.1 MPa; an air electrode layer that covers both sides of the rigid porous layer, or both sides and end faces of the rigid porous layer provided that at least one end face is excluded; and a layered double hydroxide (LDH) separator that covers an outside of the air electrode layer; wherein i) the rigid porous layer is made of a metal or an electrically conductive ceramic, whereby the rigid porous layer itself functions as a positive electrode current collector, or ii) the rigid porous layer is made of an insulating material and is covered with a porous metal layer, whereby the porous metal layer functions as a positive electrode current collector.

Abstract: Provided is an air electrode/separator assembly including: a hydroxide ion conductive dense separator; an interface layer containing a hydroxide ion conductive material and an electron conductive material and covering one side of the hydroxide ion conductive dense separator; and an air electrode layer provided on the interface layer and including an outermost catalyst layer composed of a porous current collector and a layered double hydroxide (LDH) covering a surface thereof. The outermost catalyst layer has a porosity of 60% or more.

Abstract: Provided is an air electrode/separator assembly including a hydroxide ion conductive dense separator and an air electrode layer provided on one side of the hydroxide ion conductive dense separator. The air electrode layer includes: an internal catalyst layer provided closer to the hydroxide ion conductive dense separator and filled with a mixture containing a hydroxide ion conductive material, an electron conductive material, an organic polymer, and an air electrode catalyst (provided that the hydroxide ion conductive material may be the same material as the air electrode catalyst, and provided that the electron conductive material may be the same material as the air electrode catalyst); and an outermost catalyst layer provided away from the hydroxide ion conductive dense separator having a porosity of 60% or more, composed of a porous current collector and a layered double hydroxide (LDH) covering a surface thereof.

Abstract: Provided is a layered-double-hydroxide-(LDH) containing composite material including a porous substrate and a high density LDH-containing functional layer on and/or in the porous substrate. The LDH-containing composite material of the present invention includes the porous substrate and the functional layer formed on and/or in the porous substrate. The functional layer contains a layered double hydroxide represented by the general 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 represents an integer not less than 1, x represents a value of 0.1 to 0.4, and m represents a value not less than 0) and has water impermeability.

Abstract: Provided is a negative electrode for use in a zinc secondary battery containing (A) ZnO particles and (B) at least two selected from the group consisting of (i) metallic Zn particles having an average particle size D50 of 5 to 80 ?m, (ii) at least one metal element selected from In and Bi, and (iii) a binder resin having a hydroxyl group.

Abstract: Disclosed is an air electrode for a metal-air battery, the air electrode including a separator composed of a hydroxide-ion-conductive inorganic solid electrolyte being a dense ceramic material, and an air electrode layer disposed on the separator and containing an air electrode catalyst, an electron-conductive material, and a hydroxide-ion-conductive material, or containing an air electrode catalyst also serving as an electron-conductive material and a hydroxide-ion-conductive material. According to the present invention, the reaction resistance of the air electrode including the dense ceramic separator can be significantly reduced in a metal-air battery while ensuring the desired characteristics of the dense ceramic separator.

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 layered-double-hydroxide-(LDH) containing composite material including a porous substrate and a high density LDH-containing functional layer on and/or in the porous substrate. The LDH-containing composite material of the present invention includes the porous substrate and the functional layer formed on and/or in the porous substrate. The functional layer contains a layered double hydroxide represented by the general 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 represents an integer not less than 1, x represents a value of 0.1 to 0.4, and m represents a value not less than 0) and has water impermeability.

Abstract: Provided is a layered-double-hydroxide-(LDH) containing composite material including a porous substrate and a high density LDH-containing functional layer on and/or in the porous substrate. The LDH-containing composite material of the present invention includes the porous substrate and the functional layer formed on and/or in the porous substrate. The functional layer contains a layered double hydroxide represented by the general 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 represents an integer not less than 1, x represents a value of 0.1 to 0.4, and m represents a value not less than 0) and has water impermeability.

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 an air electrode or water electrolysis anode showing a higher catalytic activity than carbon black and not having a risk of oxidative degradation, in particular, an air electrode or water electrolysis anode for a metal-air battery or a water electrolysis apparatus. The air electrode or water electrolysis anode includes an electron-conductive material represented by LaNi1?x?yCuxFeyO3?? (where x>0, y>0, x+y<1, and 0???0.4).