Abstract:

A compact PbS quantum-dot thin film was prepared using the combination of TiO₂ nanorod arrays and 1, 2-ethanedithiol following the spin-coating assisted successive ionic layer absorption and reaction procedure. Solar cells with the novel structure of FTO/compact PbS quantum-dot thin film sensitized TiO₂ nanorod arrays/spiro-OMeTAD/Au were assembled. Subsequently, the influence of the length of TiO₂ nanorod arrays on the photovoltaic performance of all-solid-state compact PbS quantum-dot thin film sensitized solar cells was evaluated. The corresponding solar cells having TiO₂ nanorod array lengths of 290, 540, and 1040 nm achieved photoelectric conversion efficiencies (PCE) of 2.02%, 4.81%, and 1.95%, respectively. These results reveal that in order to achieve high PCE values with the all-solid-state quantum dot sensitized solar cells, it is very important to balance the hole diffusion length with the loading amount of quantum-dots.

Key words: Compact PbS quantum-dot thin film, TiO₂ nanorod array, 1, 2-Ethanedithiol, Successive ionic layer adsorption and reaction, Solid-state quantum-dot sensitized solar cell