There is provided a functional layer including a layered double hydroxide. The functional layer further contains titania.

There is provided a functional layer including a layered double hydroxide. The functional layer further contains titania.

There is provided a functional layer including a layered double hydroxide, which is composed of: a plurality of basic hydroxide layers including Ni, Al, Ti, and OH groups; and intermediate layers composed of anions and H.sub.2O, each intermediate layer being interposed between two adjacent basic hydroxide layers.

There is provided a functional layer including a layered double hydroxide, which is composed of: a plurality of basic hydroxide layers including Ni, Al, Ti, and OH groups; and intermediate layers composed of anions and H.sub.2O, each intermediate layer being interposed between two adjacent basic hydroxide layers.

There is provided a functional layer including a layered double hydroxide. The layered double hydroxide does not undergo a change in the surface microstructure and the crystalline structure when immersed in 5 mol/L of an aqueous potassium hydroxide solution containing zinc oxide in a concentration of 0.4 mol/L at 70 C. for three weeks.

There is provided a functional layer including a layered double hydroxide. The layered double hydroxide does not undergo a change in the surface microstructure and the crystalline structure when immersed in 5 mol/L of an aqueous potassium hydroxide solution containing zinc oxide in a concentration of 0.4 mol/L at 70 C. for three weeks.

There is provided a functional layer including a layered double hydroxide that contains Ni, Al, Ti and Zn, and has an atomic ratio Zn/(Ni+Ti+Al+Zn) of 0.04 or more determined by an energy dispersive X-ray analysis (EDS).

There is provided a functional layer including a layered double hydroxide that contains Ni, Al, Ti and Zn, and has an atomic ratio Zn/(Ni+Ti+Al+Zn) of 0.04 or more determined by an energy dispersive X-ray analysis (EDS).

There is provided a functional layer including a layered double hydroxide (LDH). The functional layer includes a first layer with a thickness of 0.10 m or more, the first layer being composed of fine LDH particles having a diameter of less than 0.05 m, and a second layer composed of large LDH particles having a mean particle diameter of 0.05 m or more, the second layer being an outermost layer provided on the first layer.

There is provided a functional layer including a layered double hydroxide (LDH). The functional layer includes a first layer with a thickness of 0.10 m or more, the first layer being composed of fine LDH particles having a diameter of less than 0.05 m, and a second layer composed of large LDH particles having a mean particle diameter of 0.05 m or more, the second layer being an outermost layer provided on the first layer.