Influence of Adding Room Temperature Solid Base in the Electrolyte for the Fabrication and Characterization of Solid-State Dye-Sensitized Solar Cells

The nature and concentration of suitable bases in the electrolyte of the dye-sensitized solar cells (DSSCs) have been advocated to control their performance. In this work, performance optimization was attempted utilizing a room-temperature solid base in the liquid-electrolyte for solid-state (ss)-DSSCs, which were fabricated by slowly evaporating the liquid-electrolyte at room temperature. It was found that excess base amount in liquid-electrolyte led to dye-TiO
2
ester linkage and decreased the short-circuit current density of ss-DSSC. The optimal amount of 1-methylbenzimidazole was 0.1 M reducing the performance gap between liquid-state DSSC and ss-DSSC. The efficiency of ss-DSSCs at 0.5 M addition was 68 % of liquid-state DSSCs although it dramatically improved to 94 % of liquid-state DSSCs at 0.1 M addition.