Highly structured TiO/In(OH)S/PbS/PEDOT:PSS for photovoltaic applications

A system of highly structured TiO 2 /In(OH) x S y /PbS/PEDOT:PSS has been developed and investigated by photovoltage spectroscopy, X-ray photo- and Auger electron spectroscopies, electron microscopy, and photovoltaic response. TiO 2 , In(OH) x S y , PbS, and PEDOT:PSS serve as electron conductor, buffer layer, absorber, and hole conductor, respectively. Both buffer and absorber layers were prepared by chemical bath deposition. The band gap of as-prepared In(OH) x S y varied between 2.4 and 3.5 eV depending on the pH-value of the solution. In addition, the band gap of the PbS could be widened to about 0.85 eV making the application as absorber for solar cells feasible. At present, corresponding solar cell devices reach short-circuit current densities of about 8 mA/cm 2 and open-circuit voltages of about 0.3 V.