RIS ID
104532
Abstract
Photochemical upconversion based on triplet-triplet annihilation (TTA-UC) is employed to enhance the short-circuit currents generated by two varieties of thin-film solar cells, a hydrogenated amorphous silicon (a-Si:H) solar cell and a dye-sensitized solar cell (DSC). TTA-UC is exploited to harvest transmitted sub-bandgap photons, combine their energies and re-radiate upconverted photons back towards the solar cells. In the present study we employ a dual-emitter TTA-UC system which allows for significantly improved UC quantum yields as compared to the previously used single-emitter TTA systems. In doing so we achieve record photo-current enhancement values for both the a-Si:H device and the DSC, surpassing 10-3 mA cm-2 sun-2 for the first time for a TTA-UC system and marking a record for upconversion-enhanced solar cells in general. We discuss pertinent challenges of the TTA-UC technology which need to be addressed in order to achieve its viable device application.
Publication Details
Cheng, Y. Yap., Nattestad, A., Schulze, T. F., MacQueen, R. W., Fückel, B., Lips, K., Wallace, G. G., Khoury, T., Crossley, M. J. & Schmidt, T. W. (2015). Increased upconversion performance for thin film solar cells: A trimolecular composition. Chemical Science, 7 (1), 559-568.