Dimensionally stable anode for the electrowinning of aluminum

An anode for the electrolysis of aluminum having an outer layer of a ceramic material and a core of a composite material, where said composite material comprises an electronic conducting material and a ceramic material arranged in a continuous network,

• wherein the ceramic material in the composite is of the same type as that of the outer layer, wherein the ceramic material has the composition A1+X(B1+δCd)O4, where A is a divalent cation or mixture of cations, B is a trivalent cation or a mixture of cations, and C is a trivalent cation or mixture of cations or tetravalent cation, O is the element oxygen, for C trivalent;
• x=0, 0<d<1, δ<0.2 and x+d+δ is essentially equal to 1, for C tetravalent;
• 0.4<x<0.6, 0.4<d<0.6, δ<0.2 and x+d+δ is essentially equal to 1, and that the electronic conducting material comprises Ag optionally alloyed or mixed with other conducting materials.