Design Of P-type Organic Dyes For Dye-sensitized Solar Cells

The efficiency of the dye-sensitized solar cells decides this cells' wide application in the world,however,the efficient dyes play a key role in affecting its efficiency.Therefore,designing p-type dye with high oscillator strength and broader absorption spectrum is the most urgent affair.In this paper,based on an experimentally synthesized p-type dye QT-1,this work design a series of dyes by modifying the ?-linker and the donor.By using the density functional theory,we investigate their electronic and optical properties,etc.The main content of this paper is as follows:(1)This work design dyes SPL401-SPL407 by modifying the ?-linker between the donor and the acceptor.The results indicate that compared to dye QT-1,dyes SPL406 and SPL407 respectively have 141 nm and 110 nm red-shift,70% and 80% increased oscillator strength,and the broader absorption spectra covering the entire visible range to the near-IR region of 1200 nm.The adsorption energy indicates that dye SPL407 can strongly be adsorbed on NiO surface.(2)Through inserting additional acceptor groups,this work design three D-A-?-A structured dyes ME18-ME20.The results reveal that dye ME20 have 152 nm red-shift,78% increased oscillator strength,and the broader absorption spectrum region even up to 1400 nm,however,dye ME18 have the decreased oscillator strength by 34%.The adsorption energy indicates that the dye ME20 can strongly be adsorbed on NiO surface.(3)By using additional donor groups,this work design dyes ME21-ME28.The results infer that dye ME25 have obvious red-shift and highly improved oscillator strength,and there are strong interaction between dyes and NiO surface.