Abstract:
Kesterite materials (Cu2ZnSnS/Se or CZTS) exhibit encouraging potentials for
energy conversion. In this study inexpensive, and cost-effective kesterite-derived
nanostructures through metal doping in (CuZnXS, X=Ce, La, Mo) has been
synthesized and test them as photo-absorbing materials for semiconductor-based thin film solar cell applications. The photo-absorbance or light-absorption propensity of
the photo-anode material in a solar cell is essential to the overall effectiveness of the
solar cell. By adding a second layer of photo absorbance material, the photo-anode
activity can be increased, which may also increase the amount of photogenerated
electrons. Optical spectroscopy methods, such as UV-visible spectroscopy, is used to
examine the photo absorption characteristics of the synthesized nanostructures. The
optical band gap, % transmittance, extinction coefficient and refractive index of the
kesterite material has been calculated and it was found that the band gap of the as
synthesized kesterite material is varies in the range 1.125eV -1.5eV which is suitable
as the absorber material for solar cell applications. The structural defects and
recombination centers are examined using Photoluminescence spectroscopy. X-ray
diffraction (XRD) and Raman Spectroscopy has been done to study the structure
parameters and vibrational modes of the as synthesized kesterite material. The XRD
patterns of the materials shows the formation of kesterite material with tetragonal
structure for Ce-CuZnS and Mo-CuZnS and kesterite with monoclinic structure for
La-CuZnS. The Raman spectra of all samples shows the characteristics modes of Cu-
xi
S, Zn-S and Ce2O, La-O and different modes of S-Mo-S in Ce-CuZnS, La-CuZnS,
and Mo-CuZnS respectively.
