Patent ID: 11969712
Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
Field: Chemical engineering (Chemistry)
Classification: CPC B | IPC B

Claim 1:
2. The catalyst for purification of exhaust gas according to claim 1, wherein a Ce concentration β in the vicinity of the Pd-based nanoparticles is 16% or more, wherein the Ce concentration β is determined, based on an element mapping image obtained by energy dispersive X-ray analysis, by the following formula (2):, β
     =
     
      
       1
       n
      
      ⁢
      
       
        ∑
        
         k
         =
         1
        
        n
       
       
        (
        
         
          C
          
           C
           ⁢
           e
          
         
         /
         
          (
          
           
            C
            Pd
           
           +
           
            C
            Al
           
           +
           
            C
            Ce
           
           +
           
            ∑
            
             C
             M
            
           
          
          )
         
         ×
         100
        
        )
       
      
     
    
   
   
    
     (
     2
     )
    
   
  
 

in the formula (2), n is a total number of regions of 162.0 nm in length x 162.0 nm in width centered on the Pd-based nanoparticles randomly extracted in the element mapping image, and CCe, CPd, CAl, and CM represent concentrations of Ce, Pd, Al, and other metal M in respective extracted regions.