Patent ID: 7148394

Claim:
A process for synthesis of a cesium based ceramic with a hollandite structure with the following formula: A x B y (C 1 z1 , C 2 z2 )D t O 16 in which: A represents the monovalent element Cs, possibly partly substituted by at least one other monovalent element, B represents the divalent element Ba, possibly partly substituted by at least one other divalent element, C 1 represents the trivalent element aluminium, possibly partly substituted by at least one other trivalent element, C 2 represents the trivalent element iron and/or chromium, possibly partly substituted by at least one other trivalent element, D represents at least one element chosen in a group consisting of tetravalent titanium, divalent, trivalent or tetravalent manganese, pentavalent niobium and pentavalent antimony and mixtures thereof, x, y, z1, z2 and t are such that: 0.1≦x≦0.5 0.5≦y≦1.1 1 ≦z 1 +z 2≦2.5 , z 1 and z 2 are both not equal to zero, 5≦t≦7, x, y, z1, z2, t are chosen such that the positive charges of the elements A, B, C 1 , C 2 and D compensate for the negative charges added by oxygen, the said process comprising the following sequence of steps: a) prepare a precipitate containing A, B, C 1 , C 2 and D by mixing a solution of mixed alcoxide containing C 1 and D and a saline aqueous solution containing A, B, C 2 , in stoichiometric proportions; b) sinter the precipitate from step a) at a temperature of 1150 to 1350° C.