A Cation‐Exchange Approach for the Fabrication of Efficient Methylammonium Tin Iodide Perovskite Solar Cells. (2nd April 2019) - Li, Fengzhu
Abstract: Tin‐based halide perovskite materials have been successfully employed in lead‐free perovskite solar cells, but the overall power conversion efficiencies (PCEs) have been limited by the high carrier concentration from the facile oxidation of Sn 2+ to Sn 4+ . Now a chemical route is developed for fabrication of high‐quality methylammonium tin iodide perovskite (MASnI3 ) films: hydrazinium tin iodide (HASnI3 ) perovskite film is first solution‐deposited using presursors hydrazinium iodide (HAI) and tin iodide (SnI2 ), and then transformed into MASnI3 via a cation displacement approach. With the two‐step process, a dense and uniform MASnI3 film is obtained with large grain sizes and high crystallization. Detrimental oxidation is suppressed by the hydrazine released from the film during the transformation. With the MASnI3 as light harvester, mesoporous perovskite solar cells were prepared, and a maximum power conversion efficiency (PCE) of 7.13 % is delivered with good reproducibility. Abstract : Hochwertige, Pinhole‐freie CH3 NH3 SnI3 ‐Filme werden aus reinem NH2 NH3 SnI3 ‐Perowskit erhalten. Bei der Umwandlung wird innerhalb der Filme das Reduktionsmittel Hydrazin erzeugt, das die Oxidation von Sn 2+ zu Sn 4+ unterdrückt. Mit dem CH3 NH3 SnI3 ‐Film als Lichtabsorber wurden mesoporöse MASnI3 ‐Perowskitsolarzellen mit einem maximalen PCE von 7.13 % hergestellt.