Fresh fruits of ivy gourd (C. indica) and flowers of red frangipani
(P. rubra) were collected from the Pondicherry University
campus, Puducherry, India in May 2012. Fresh fruits of ivy gourd
were taken and washed with de-ionized water. After removing
the seeds, the flesh of ivy gourd fruits has been kept in liquid
nitrogen for few minutes then crushed using mortar and pestle
until to get fine paste. The paste was vacuum dried at 60 C to
remove the moisture then crushed using mortar and pestle into
fine powder. About 1 g of fine powder was dissolved in 50 mL of
absolute ethanol at room temperature and kept undisturbed in
dark for 24 h. Solid residue was filtrated out to obtain clear
dye solution. The fresh red frangipani flowers were washed with
de-ionized water and then vacuum dried at 60 C. The dried red
frangipani flowers were crushed using mortar and pestle into
fine powder and 1 g of the powder was immersed in 50 mL pure
ethanol and kept undisturbed in dark for 24 h. Solid residue was
filtrated out and the resulting dye solution was used as sensitizers.
The extracted dyes were properly stored, protected from direct
sunlight, and used for further characterization and as
sensitizers in DSSCs.
UV–Vis absorption spectra of the extracted dye solutions and
dyes after adsorbed onto TiO2 surface were recorded using a UV-
2450 (Shimadzu) spectrophotometer. Fourier transform infrared
(FTIR) spectra (Thermo Nicolet 6700 FTIR) of the powders obtained
from the dried fruits of ivy gourd (C. indica) and flowers of red frangipani
were recorded using KBr technique. Fourier transform Raman
spectrum (Bruker RFS 27) for the powder obtained from the
dried fruits of ivy gourd was recorded with excitation at
1064 nm using Nd: YAG laser. High resolution liquid chromatography–mass
spectrometer (Shimadzu LC–MS-2010) was used to record
spectra of the extract obtained from the flowers of red
frangipani.