Catalyst for fuel cell oxygen electrodes
A catalyst having catalytically active material supported on a carrier matrix. The catalytically active material may be a mixed-valence, nanoclustered oxide(s), an organometallic material or a combination thereof. The supported catalytic material is particularly useful for catalyzing oxygen reduction in a fuel cell, such as an alkaline fuel cell.
1. A supported catalyst for an alkaline fuel cell comprising:
a carrier matrix; and
an active catalytic material supported by said carrier matrix, said active catalytic material including a mixed valence, nanoclustered metal oxide layer and an organometallic layer, said nanoclustered metal oxide layer and said organometallic layer being supported on said carrier matrix;
said mixed-valence, nanoclustered metal oxide comprising cobalt-manganese oxides.
2. The supported catalyst according to claim 1 , wherein said carrier matrix is carbon based.
3. The supported catalyst according to claim 1 , wherein said mixed-valence, nanoclustered metal oxide is multi-component and multifunctional with one component providing a rate of reaction favoring a first reaction step and another component providing a rate of reaction favoring a second reaction step over the first.
4. The supported catalyst according to claim 1 , wherein said mixed-valence, nanoclustered metal oxide includes more metals in a lower oxidation state than metals in a higher oxidation state.
5. The supported catalyst according to claim 1 , wherein said mixed valenced nanoclustered metal oxide includes three or more valences.
6. The supported catalyst according to claim 1 , wherein said mixed valenced nanoclustered metal oxide includes four or more valences.
7. The supported catalyst of claim 1 , wherein said mixed valenced nanoclustered metal oxide includes a plurality of grains having different orientations.
8. The supported catalyst according to claim 7 , wherein said grains each have a diameter of 100 A or less.
9. The supported catalyst according to claim 1 , wherein said organometallic comprises a macrocycle including at least one transition metal.