Schottky Solar Cells with CuInS₂ Nanocrystals as Absorber Material

Colloidal semiconductor nanocrystals with tunable optical properties are promising materials for light harvesting in solar cells. So far, in particular cadmiumand lead chalcogenide nanocrystals were intensively studied in this respect, and the device performance has made rapid progress in recent years. In contrast, less research efforts were undertaken to develop solar cells based on Cd- and Pb-free nanoparticles as absorbermaterial. In the present work, we report on Schottky solar cells with the absorber layermade of colloidal copper indiumdisulfide nanocrystals. Absorber films with up to ∼ 500 nm thickness were realized by a solution-based layer-by-layer deposition technique. The device performance was systematically studied dependent on the absorber layer thickness. Decreasing photocurrent densities with increasing thickness revealed charge transport to be a limiting factor for the device performance