Phycoerythrobilin/phycourobilin as efficient sensitizers of dye-sensitized solar cell

Abstract

The power conversion efficiency (PCE) of phycoerythrobilin (PEB) and phycourobilin (PUB) as sensitizers of dye-sensitized solar cells is investigated by employing the first-principles calculations. We constructed a model for the adsorption of PEB/PUB on the surface of TiO2 in three different ways. The geometrical configurations of the PEB/PUB-TiO2 complexes are optimized, and the electronic properties are determined based on the first-principles calculations. The short-circuit current density, open-circuit voltage, and filling factor are obtained based on the band alignments of the complex and the optical absorptions of PEB/PUB. The D149 dye is used to assess the validity of our method. The obtained PCE of 5.56 % corresponds to the experimental 5.4 %, confirming the credibility of the current method. The highest PCEs of PUB and PEB are predicted at 11.05 % and 9.73 %, which implies that the two molecules are promising candidate sensitizers of the dye-sensitized solar cell.