Abstract:
In solid-state solar cells, binary structure Sb2S3 semiconductor material is much
more attractive as a light-harvesting active layer due to its desirable properties in
solar cell applications. Since the precursor solution of the active layer is one of the
key parameters that would control the material properties and hence device
performance, in this study, we investigated the effect of the precursor
concentration of the Sb2S3 solution. The Sb2S3 complex precursor solutions were
prepared by adding 1mmol of Sb2Cl3 and 1.5 mmol of thiourea in different volumes
(0.5, 1, 1.5 ml) of solvent (2-methoxyethanol), which give the concentrations of 2,
1, and 0.67 M of Sb2S3 complex precursor solution. The devices were fabricated
in the configuration of FTO/TiO2/Sb2S3/P3HT/Ag. The physical and electrical
properties of the devices were examined based on the influence of the precursor
concentration of Sb2S3 solution by measurements of current density-voltage (J-V),
External Quantum Efficiency (EQE), UV-Vis absorption spectroscopy, and
Scanning Electron Microscopy (SEM). The power conversion efficiencies (PCE)
of 0.75, 3.23, and 2.11% were obtained for 2, 1, and 0.67 M, respectively. The best
device performance was achieved with 1 M of Sb2S3 solution, which was 53% and
higher than low concentrated (0.67 M) Sb2S3 solution and 3 times higher than the
higher concentration (2 M) of Sb2S3 solution indicating the significant role of the
precursor concentration.
