Author(s)

Daniel Ogermann, Thorsten Wilke, Karl Kleinermanns

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Institute of Physical Chemistry, Heinrich-Heine-University, Duesseldorf, Germany.

Gr?tzel cells were prepared by using CdSe- and CdSxSey-nanoparticles as sensitizer. The quantum dots were incorporated in various sizes and concentrations in a TiO2 nanoparticle layer by a simple mixing procedure. The advantage of this method compared to anchoring of nanoparticles to TiO₂ by linker molecules or chemical bath deposition is that we are able to control the ratio between TiO₂ and CdSe or CdS_xSe_y more precisely and over a larger range of concentrations. TiO₂ solar cells sensitized by this technique achieved photon-to-current conversion efficiencies (IPCE) of ~40% in the range of 300 - 500 nm with a maximum IPCE of ~70% at 400 nm (sulphide/sulphate electrolyte). The best results at wavelengths above 500 nm were achieved with CdS_xSe_y/TiO₂ cells at a molar ratio of 6:1 (S:Se) with IPCE of 40% at 500 nm and still 15% at 800 nm. Quantum efficiencies obtained with iodine/iodide electrolyte were lower and lead to an overall efficiency of 0.32%. The CdSxSey sensitized solar cells show enhanced stability compared to CdSe based systems and the use of the iodine/iodide electrolyte increases cell endurance further.

Solar Cells; Nanocomposites; Cadmium Selenosulphide; Titanium Dioxide

D. Ogermann, T. Wilke and K. Kleinermanns, "CdS_xSe_y/TiO₂ Solar Cell Prepared with Sintered Mixture Deposition," Open Journal of Physical Chemistry, Vol. 2 No. 1, 2012, pp. 47-57. doi: 10.4236/ojpc.2012.21007.