Combined experimental and DFT–TDDFT study of photo-active constituents of Canarium odontophyllum for DSSC application

The active constituents of Canarium odontophyllum (COP) were investigated experimentally and theoretically for dye sensitized solar cell (DSSC) application. Three main flavonoid pigments (cyanidin, pelargonidin and maritimein) were detected in COP showing photo-energy conversion efficiencies of 1.43%, 0.87% and 0.60%, respectively. The molecular geometries, electronic structures, optical absorption spectra and proton affinity of these molecules were investigated with DFT/TDDFT. All three molecules displayed π→π* transition dominant in HOMO→LUMO transition. The anchoring groups onto TiO2 surface were deduced from combined experimental and calculated data. All the constituents of COP are potential sensitizers for DSSC.