| 초록 |
The hybrid organic-inorganic lead halide perovskite(CH3NH3PbI3) has a high absorption coefficient, high crystallinity at low temperature, and long range of balanced electron-hole transport length. However, Pb compounds have problems with the toxicity. Sn based perovskite in particular received much attention as an alternative light-harvesting active layer material instead of Pb based perovskite in photovoltaic cells. Pb-free perovskite solar cells based on methylammonium tin iodide(CH3NH3SnI3) as the light harvester are reported. However, it is well known that the 2+ state is easily become to 4+ states. Therefore important problem with the use of Sn perovskite is their chemical instability in air. A2SnI6 (A=Cs,CH3NH3) structure is good candidate for making more stable Sn based perovskite solar because A2SnI6 consist with Sn 4+ state. In this work, we demonstrate (CH3NH3)2SnI6 as a Pb-free hybrid halide perovskite film for the light harvesting semiconductor in photovoltaic applications. |
