A photosensitizer dye is provided. The photosensitizer dye contains a Ru complex represented by the following formula (1):
wherein Y
1
and Y
2
independently represents hydrogen atom (H), lithium (Li), sodium (Na) or tetra-alkyl ammonium groups (as represented by the following general formula (2)). Formula (2):
wherein A, B, C and D independently represents C
m
H
2m+1
(m=1˜6).
Wherein X
1
represents one of the following formulas (3)˜(8) and X
2
represents H or a group the same as X
1
,