Patent ID: 7883820

Claim:
An ion-conductive inorganic membrane comprising: phosphate platelets; at least one silicon compound selected from the group consisting of silicate, siloxane, and silane; and a Keggin type polyoxometalate and/or a Keggin-type heteropoly acid, wherein: the phosphate platelets are three-dimensionally connected to each other via the at least one silicon compound, the Keggin-type heteropoly acid is an acid selected from the group consisting of H 4 SiW 12 O 40 , H 4 SiMo 12 O 40 , H 5 SiVMo 11 O 40 , H 6 SiV 2 Mo 10 O 40 , H 7 SiV 3 Mo 9 O 40 , H 3 PMo 12 O 40 , H 3 PW 12 O 40 , (VO) 1.5 PMo 12 O 40 , (VO) 1.5 PW 12 O 40 , (TiO) 1.5 PMo 12 O 40 , H(VO)PMo 12 O 40 , H(VO)PW 12 O 40 , H 6 PV 3 Mo 9 O 40 , H 5 PV 2 Mo 10 O 40 , H 5 PV 2 W 10 O 40 , H 6 PV 3 W 9 O 40 , H 4 PV 2 Mo 11 O 40 , H 4 PVW 11 O 40 , RhPMo 12 O 40 , BiPMo 12 O 40 , HCrPVMo 11 O 40 , HBiPVMo 11 O 40 , and a combination thereof, and the Keggin-type polyoxometalate is a salt formed by substituting protons of the Keggin-type heteropoly acid with one of alkali metal ions and ammonium ions.