HIT intermediate-band solar cells with self-assembled colloidal quantum dots and metal nanoparticles

摘要

The particular opto-electronic properties of chemically synthesized colloidal nanoparticles can be promising for functional materials, as those required for high efficient photovoltaic (PV) devices. In particular, appropriately-designed semiconductor colloids (quantum dots, QDs) can potentially allow sub-bandgap current generation in intermediate-band solar cells; while metal nanoparticles (MNPs) sustaining surface plasmons can provide both near and far-field light trapping to further boost the generated power. However, the incorporation of colloidal particles in inorganic PV materials is not trivial,\udtherefore their implementation has so far been restricted to\udorganic/polymeric based solar cells. In this work, PbS colloidal\udQDs have been incorporated in the intrinsic a-Si:H layer of HIT\ud(substrate/a-Si:H hetero-junction) test structures. Both c-Si and\udGaAs substrates have been used, and in some cases colloidal Au\udNPs have also been included. The obtained devices are meant as\udprobes to verify the feasibility of incorporating foreign\udnanoparticles in a cell structure and not as potentially efficient\udsolar cells. Despite the radical novelties incorporated, the devices\udbehaved similarly to the references, thus proving the\udcompatibility of the proposed materials and processes.