On the study of dye sensitized solar cells with high light harvesting efficiency and correlation of its chemical reactivity parameters with overall performance

Abstract

Abstract In this study, thirteen donors with the same spacer and acceptor have been tested to model dyes for dye sensitized solar cell (DSSC). Amongst the thirteen donors, 7,7,13,13-tetramethyl-8,9,12,13-tetrahydro-2H,5H,7H,11Hpyrano[2′,3′:4,5]pyrano[2,3-f]pyrido[3,2,1-ij]quinoline-2,5-dione is found to possess the highest oscillator strength amongst the other dyes in first excited state. This donor has been studied further with five different acceptors, among which, the dye with rhodanine acetic acid acceptor as well as its conformer have the lowest HOMO-LUMO energy gap (Eg), highest absorption wavelength in the UV-visible spectrum with high oscillator strength and low exciton binding energy in the first excited state as compared to the other four dyes considered here. The rhodanine acetic acid based dyes have shown to outperform all the other four dyes in terms of chemical reactivity parameters. All the six dyes when tested further with the inclusion of an extra benzene spacer show enhanced overall performance, with the rhodanine acetic acid based dyes showing the most planarity, highest absorption wavelength, more suitable reactivity parameters etc. Correlation studies between the solar cell parameters and chemical reactivity parameters have also been conducted where a direct relationship between the chemical hardness of the dye and open circuit voltage has been observed.