Study on the spectral complementary composite dye molecules designed for high performance dye-sensitized solar cells: A theoretical investigation

Abstract

There are many strategies to improve the efficiency of DSSCs, the most impactful way is to promote the effective light capturing, such as widening the spectral absorption range and/or enhancing the spectral absorption intensity. In this paper, we are inspired by Hagfeldt and his coworkers' work, and designed several spectral-complementary D-pi-A dyes for high performance dye-sensitized solar cells. What's more, we studied the designed and the experimental dyes using density functional theory and time-dependent density functional theory. The electronic properties, including frontier molecular orbital, intra-molecular charge transfer, absorption spectra, are investigated. Our results show that the designed dye B1 have the best absorption complementarity with dye XY1, and correspondingly induces higher light-harvesting performance in the range of the solar spectrum. The dye-sensitized solar cells using B1 and XY1 as sensitizers is predicted to be higher performance than the combination of other dyes. Our work is expected to assist to prepare high performance dye-sensitized solar cells.