Organic-inorganic halide perovskites: perspectives for silicon-based tandem solar cells

0439580 - FZÚ 2015 RIV US eng J - Journal Article
Löper, P. - Niesen, B. - Moon, S.J. - Martin de Nicolas, S. - Holovský, Jakub - Remeš, Zdeněk - Ledinský, Martin - Haug, F.J. - Yum, J. H. - De Wolf, S. - Ballif, C.
Organic-inorganic halide perovskites: perspectives for silicon-based tandem solar cells.
IEEE Journal of Photovoltaics. Roč. 4, č. 6 (2014), s. 1545-1551. ISSN 2156-3381. E-ISSN 2156-3403
R&D Projects: GA MŠMT(CZ) LM2011026
Institutional support: RVO:68378271
Keywords : perovskite * tandem solar cells * optical absorption * photothermal deflection spectroscopy * degradation
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 3.165, year: 2014

Using highly sensitive photothermal deflection spectroscopy, we measure the absorption spectrum of CH3NH3PbI3 perovskite films at room temperature. We find a band edge with a particularly steep absorption tail, translating into an Urbach energy as small as 15 meV. The sub-bandgap optical absorption is below the detection limit i.e. <1 cm-1. These results confirm the excellent electronic properties of organometallic halide perovskite thin films, resulting in very high open-circuit voltages obtained for perovskite solar cells. The shape of the absorption edges proves that it has a direct bandgap, with bandgap of about 1.55 eV. Following intentional moisture ingress, we find that the absorption at photon energies below 2.5 eV is strongly reduced, suggesting a compositional change of the deposited material. The very low subgap absorption together with open-circuit voltages >1.1 V renders perovskite solar cells a promising option for Si-based tandem solar cells.
Permanent Link: http://hdl.handle.net/11104/0242833