Large Enhancement of Dye Sensitized Solar Cell Efficiency by Co-sensitizing Pyridyl- and Carboxylic Acid-Based Dyes

Co-sensitization is an attractive approach to enhance the light-harvesting efficiency of a dye sensitized solar cell (DSSC), whereby two or more dyes having complementary absorption spectra are co-adsorbed within a DSSC. A new method of co-sensitizing simultaneously pyridyl- and carboxylic acid-based dyes was performed and proved to be a successful approach for increasing the photoconversion efficiency (PCE%) of a DSSC. Yellow and red pyridyl-based dyes (T181 and T202) were co-sensitized with a blue carboxylic acid-based dye (Dyenamo Blue, DB). The co-sensitized DSSCs showed profound performance enhancements with a cobalt tris­(bipyridine) electrolyte system. Increases in the total cell efficiency of 45% and 16% were seen in the co-sensitized T181-DB and T202-DB cells when compared to the single dye-sensitized DB cell, respectively. Remarkable increases in photocurrent (<i>J</i>_sc) and photovoltage (<i>V</i>_oc) were seen in both co-sensitized cells. The higher <i>V</i>_oc values were mainly due to the decrease in the electron recombination processes at the TiO₂/cobalt electrolyte interface. The increase in dye coverage in the co-sensitized cells resulted in a blocking behavior at the TiO₂/electrolyte interface and had positive effects on electron lifetime. In addition the higher <i>J</i>_sc values were associated with the complementary absorption responses of T181 and T202 with DB as mirrored in the IPCE% spectra

Improvement in dye sensitized solar cells from past to present

Several emerging renewable technologies are available to satisfy the current energy demand and to minimize the effect of environmental degradation caused by high consumption of fossil fuels. These technologies are not mature enough to solve this problem but require more time for improving the efficiency, and cost reduction to become the economical alternative of fossil fuels. In this paper Dye-sensitized solar cell (DSSC) has been discussed in detail owing to advancement in the technology. Since each component of DSSC is responsible for a specific function, therefore, comprehensive literature studies has been done on individual section to understand the technology in depth. All the advancement in sensitizer, semiconductors, electrolyte, electrodes, additives, sealing and anchoring groups are included in this review with performance parameter of DSSC. Focus of this article is to provide summary of all available literature since beginning to date