Anatase (TiO2) thin layers for solar energy conversion

This paper describes the possibilities of obtaining nanostructured TiO
₂
using Spray Pyrolysis Deposition and its application in a solid state solar cell (FTO/ TiO
₂
In
₂
S
₃
/ CuSbS
₂
/ graphite). Nanostructured TiO
₂
films are deposited from ethanolic solution of titanium (IV) isopropoxid, (TTIP, 99.99%, Sigma-AIdrich), and acetilacetonate, (AcAc, 99+%, Aldrich); two parameters are proposed for investigation: the annealing duration in air at 500degC, t
_TT
(h), and the number of sprayed sequences, No.
_p.c.
. The layers are characterised by XRD, AFM, Raman Spectroscopy, UV-VIS Spectroscopy and the cells by current-voltage measurement in dark and under illumination. It was found that annealing and the spraying time structure can be o a method of tailoring the TiO
₂
thin films properties and can influence the photovoltaic response of the cells. The best response was obtained for the cell obtained with TiO
₂
thin films deposited with 20 number of sprayed sequences and 6 h of annealing in air at 500degC, for which the open circuit voltage is V
_oc
= 210 mV, the short circuit current is I
_Ic
= 8.13-10
^-2
mA, the values of the maximal power is defined by V
_max
= 117 mV and I
_max
= 4.64O
₂
ldr10
²
mA, corresponding to a fill factor FF = 0.318.