Photochemical cell comprising semiconductor particles sensitized with binuclear metal complex dye and electrolyte solution mainly composed of ionic liquid

A photochemical cell, comprising:

• a semiconductor particle sensitized with a binuclear metal complex dye, which is represented by the following general formula (1):
• wherein
• M represents Ru or Os,
• XN− represents an N-valent anion as a counter ion, wherein N is 1 or 2,
• represents a bidentate nitrogen-containing ligand having two carboxyl groups,
• represents a tetradentate nitrogen-containing ligand,
• represents a bidentate nitrogen-containing ligand,
• n represents an integer of from 0 to 2,
• p represents a number of the counter ions needed to neutralize a charge of the complex, and
• one or more carboxyl groups (—COOH) may be deprotonated to be a carboxyl ion (—COO−);
• and
• an electrolyte solution which comprises an ionic liquid containing (CN)4B− as an anion component, wherein the ionic liquid is the major component of the electrolyte solution.