Catalyst, electrode, membrane electrode assembly and fuel cell

Abstract

Disclosed is a catalyst, including a catalyst particle containing at least one component selected from the group consisting of gold, platinum and an gold alloy, the gold alloy containing gold and at least one element selected from transition metal elements of the fourth period, fifth period and sixth period of the Periodic Table, and a catalyst carrier carrying the catalyst particle and containing a perovskite type oxide represented by general formula (1) given below: A (1-x) B x TiO y   (1) where the element A is at least one element selected from the group consisting of Ca, Sr and Ba, the element B is at least one element selected from the group consisting of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, the molar ratio x satisfies 0<x<1, and the molar ratio y satisfies 2.7≦y≦3.

1 . A catalyst, comprising: 
 a catalyst particle containing at least one component selected from the group consisting of gold, platinum and an gold alloy, the gold alloy containing gold and at least one element selected from transition metal elements of the fourth period, fifth period and sixth period of the Periodic Table; and    a catalyst carrier carrying the catalyst particle and containing a perovskite type oxide represented by general formula (1) given below:      A (1-x) B x TiO y   (1)    where the element A is at least one element selected from the group consisting of Ca, Sr and Ba, the element B is at least one element selected from the group consisting of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, the molar ratio x satisfies 0<x<1, and the molar ratio y satisfies 2.7≦y≦3.    
   
   
       2 . The catalyst according to  claim 1 , wherein the molar ratio x satisfies 0.1≦x≦0.95.  
   
   
       3 . The catalyst according to  claim 1 , wherein the molar ratio x satisfies 0.1≦x≦0.9.  
   
   
       4 . The catalyst according to  claim 1 , wherein the molar ratio y satisfies 2.9≦y≦3.  
   
   
       5 . The catalyst according to  claim 1 , wherein the catalyst carrier includes particles having an average particle diameter falling within not smaller than 10 nm to not larger than 1 μm.  
   
   
       6 . The catalyst according to  claim 1 , wherein the catalyst carrier carries a plurality of the catalyst particles which are selected from the group consisting of particles of the gold alloy, particles of gold, and a mixture of the gold alloy particles and the gold particles, and the catalyst particles have an average particle diameter not larger than 5 nm.  
   
   
       7 . The catalyst according to  claim 1 , wherein the catalyst carrier carries a plurality of the catalyst particles which are selected from the group consisting of particles of the gold alloy, particles of gold, and a mixture of the gold alloy particles and the gold particles, and the catalyst particles have an average particle diameter falling within not smaller than 0.2 nm to not larger than 3 nm.  
   
   
       8 . The catalyst according to  claim 1 , wherein the catalyst carrier carries a plurality of the catalyst particles which are formed of platinum particles and the catalyst particles have an average particle diameter falling within not smaller than 0.2 nm to not larger than 10 nm.  
   
   
       9 . The catalyst according to  claim 1 , further comprising particles of an oxide of at least one element selected from transition metal elements of the fourth period, the fifth period and the sixth period of the Periodic Table, said oxide particles being carried on at least one of the catalyst particle and the catalyst carrier.  
   
   
       10 . The catalyst according to  claim 1 , further comprising particles of an oxide of at least one element selected from the group consisting of Mn, Co, Zr, Mo, Ru, W and Ir, said oxide particles being carried on at least one of the catalyst particle and the catalyst carrier.  
   
   
       11 . The catalyst according to  claim 1 , wherein the gold alloy contains at least one element selected from the group consisting of Pt, Ru, Ir, Mo, Fe, Co, Ni, W, Sn and Re.  
   
   
       12 . An electrode comprising a catalyst layer containing a catalyst comprising: 
 a catalyst particle containing at least one component selected from the group consisting of gold, platinum and an gold alloy, the gold alloy containing gold and at least one element selected from transition metal elements of the fourth period, fifth period and sixth period of the Periodic Table; and    a catalyst carrier carrying the catalyst particle and containing a perovskite type oxide represented by general formula (1) given below:      A (1-x) B x TiO y   (1)    where the element A is at least one element selected from the group consisting of Ca, Sr and Ba, the element B is at least one element selected from the group consisting of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, the molar ratio x satisfies 0<x<1, and the molar ratio y satisfies 2.7≦y≦3.    
   
   
       13 . The electrode according to  claim 12 , wherein the catalyst layer further contains a proton conductive material.  
   
   
       14 . The electrode according to  claim 12 , further comprising an electrically conductive porous sheet including the catalyst layer laminated thereon.  
   
   
       15 . A membrane electrode assembly, comprising: 
 a cathode including a cathode catalyst layer;    an anode including an anode catalyst layer; and    a proton conductive membrane arranged between the cathode and the anode,    wherein at least one of the cathode catalyst layer and the anode catalyst layer contains a catalyst, comprising:    a catalyst particle containing at least one component selected from the group consisting of gold, platinum and an gold alloy, the gold alloy containing gold and at least one element selected from transition metal elements of the fourth period, fifth period and sixth period of the Periodic Table; and    a catalyst carrier carrying the catalyst particle and containing a perovskite type oxide represented by general formula (1) given below:      A (1-x) B x TiO y   (1)    where the element A is at least one element selected from the group consisting of Ca, Sr and Ba, the element B is at least one element selected from the group consisting of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, the molar ratio x satisfies 0<x<1, and the molar ratio y satisfies 2.7≦y≦3.    
   
   
       16 . The membrane electrode assembly according to  claim 15 , wherein the cathode catalyst layer contains the particular catalyst and the anode catalyst layer contains a catalyst comprising an anode catalyst particle containing at least one of platinum and ruthenium and an anode catalyst carrier carrying the anode catalyst particle and containing a carbon material.  
   
   
       17 . A fuel cell, comprising: 
 a cathode including a cathode catalyst layer;    an anode including an anode catalyst layer; and    a proton conductive membrane arranged between the cathode and the anode,    wherein at least one of the cathode catalyst layer and the anode catalyst layer contains a catalyst, comprising:    a catalyst particle containing at least one component selected from the group consisting of gold, platinum and an gold alloy, the gold alloy containing gold and at least one element selected from transition metal elements of the fourth period, fifth period and sixth period of the Periodic Table; and    a catalyst carrier carrying the catalyst particle and containing a perovskite type oxide represented by general formula (1) given below:      A (1-x) B x TiO y   (1)    where the element A is at least one element selected from the group consisting of Ca, Sr and Ba, the element B is at least one element selected from the group consisting of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, the molar ratio x satisfies 0<x<1, and the molar ratio y satisfies 2.7≦y≦3.    
   
   
       18 . The fuel cell according to  claim 17 , further comprising particles of an oxide of at least one element selected from transition metal elements of the fourth period, the fifth period, and the sixth period of the Periodic Table, said oxide particles being carried on at least one of the catalyst particle and the catalyst carrier.  
   
   
       19 . The fuel cell according to  claim 17 , wherein the catalyst carrier carries a plurality of the catalyst particles which are selected from the group consisting of particles of the gold alloy, particles of gold, and a mixture of the gold alloy particles and the gold particles, and the catalyst particles have an average particle diameter not larger than 5 nm.  
   
   
       20 . The fuel cell according to  claim 17 , further comprising a fuel containing methanol and supplied to the anode.