Electrode catalyst for fuel cell and use thereof

Abstract

To provide an economical fuel cell electrode catalyst which can be used in place of platinum as a simple substance or a platinum alloy and has easy-to-control catalytic power, a molecular metal complex is used as a fuel cell electrode catalyst which molecular metal complex is a mononuclear or multinuclear coordination compound that has a particular structure, that is not a polymer compound, and that does not have a layered structure.

1 . A fuel cell electrode catalyst comprising one or more molecular metal complexes,
 each of the one or more molecular metal complexes being a metal complex (i) having a molecular weight of 2000 or less, (ii) not having a layered structure, and (iii) including a total of one or more but not more than three metal atoms and/or metal ions to each of which three or more but not more than six ligands coordinate,   each of the one or more molecular metal complexes being a metal complex other than a porphyrin derivative, in a case where (i) said each of the one or more molecular metal complexes includes one metal atom or one metal ion and (ii) four ligands coordinate to the one metal atom or the one metal ion.   
     
     
         2 . The fuel cell electrode catalyst as set forth in  claim 1 , wherein:
 the one or more molecular metal complexes include one or more molecular metal complexes selected from molecular metal complexes expressed by the following General Formulae (1) through (73):   
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         where each of L 1  through L 624  independently indicates a ligand, each of M 1  through M 194  independently indicates a metal atom or a metal ion, and the molecular metal complex expressed by the General Formula (2) is a metal complex other than a porphyrin derivative. 
       
     
     
         3 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 the one or more molecular metal complexes selected from the molecular metal complexes expressed by the General Formulae (1) through (73) include one or more molecular metal complexes selected from the molecular metal complexes expressed by the General Formulae (5) through (21).   
     
     
         4 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 said fuel cell electrode catalyst is usable in each of an anode and a cathode.   
     
     
         5 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 the one metal atom or one metal ion is a metal atom or a metal ion thereof, the metal atom being selected from the group consisting of metal atoms and metal ions of 3A group elements, 4A group elements, 5A group elements, 6A group elements, 7A group elements, 8 group elements, 1B group elements, 3B group elements, and 6B group elements in a periodic table.   
     
     
         6 . The fuel cell electrode catalyst as set forth in  claim 5 , wherein:
 the one metal atom or one metal ion is a metal atom or a metal ion thereof, the metal atom being selected from the group consisting of the metal atoms and the metal ions of the 8 group elements.   
     
     
         7 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 each of ligand atoms of the ligands indicated by L 1  through L 624  is independently a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, a phosphor atom, a sulfur atom, or a halogen atom.   
     
     
         8 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 each of the ligands indicated by L 1  through L 624  is independently selected from ligands expressed by the following Chemical Formulae (74) through (116):   
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         9 . The fuel cell electrode catalyst as set forth in  claim 2 , wherein:
 the one or more molecular metal complexes selected from the molecular metal complexes expressed by the General Formulae (1) through (73) are selected from molecular metal complexes expressed by the following Chemical Formulae (117) through (151):   
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         10 . The fuel cell electrode catalyst as set forth in  claim 9 , wherein:
 the one or more molecular metal complexes selected from the molecular metal complexes expressed by the Chemical Formulae (117) through (151) are selected from the molecular metal complexes expressed by the Chemical Formulae (131) through (138).   
     
     
         11 . A fuel cell electrode comprising a fuel cell electrode catalyst recited in  claim 1 . 
     
     
         12 . A fuel cell comprising a fuel cell electrode catalyst recited in  claim 1  independently for each of an anode and/or a cathode. 
     
     
         13 . An electric power generation method comprising the steps of:
 oxidizing a fuel through use of a fuel cell electrode catalyst recited in  claim 1 ; and/or   reducing an oxidant through use of a fuel cell electrode catalyst recited in  claim 1 .