Electrochromic material with improved lifetime

Abstract

Disclosed are viologen derivatives as an electrochromic material having improved stability and lifetime, a metal oxide electrode including the same, and an electrochromic device using the viologen derivative as an electrochromic material. The viologen derivative includes a suitable regulator group capable of increasing ΔE that is a potential difference between E 1 (potential at the first redox reaction) and E 2 (potential at the second redox reaction). When ΔE increases, the mole fraction of viologen molecules present in the second reduction state decreases. Therefore, it is possible to lower the mole fraction of viologen molecules present in an irreversibly reduced state at an applied potential, thereby increasing the lifetime of an electrochromic material and an electrochromic device.

1 - 11 . (canceled) 
   
   
       12 . A compound represented by the following formula 1: 
     
       
         
         
             
             
         
       
       wherein each of R 1 , R 2 , R 4  and R 5  independently or simultaneously represents H, a C1-C6 alkyl group, OH, OR 97 , CN, NO 2 , COOH, CO 2 R 97 , CONH 2 , CONR 98   2  or NR 98   2 ; each of R 97  and R 98  represents a C1-C6 alkyl group; and either or both of linker 1 and linker 2 may be present, as necessary. 
     
   
   
       13 . The compound according to  claim 12 , wherein the compound is represented by the following formula 1-1: 
     
       
         
         
             
             
         
       
       wherein each of R 1 , R 2 , R 4  and R 5  independently or simultaneously represents H, a C1-C6 alkyl group, OH, OR 97 , CN, NO 2 , COOH, CO 2 R 97 , CONH 2 , CONR 98   2  or NR 98   2 ; and each of R 97  and R 98  represents a C1-C6 alkyl group. 
     
   
   
       14 - 15 . (canceled)