Presentation Information
[22p-P03-7]Removing the interfacial impurity SnI4 for efficiency boost of Sn perovskite
〇Liu Jiaqi1, Liang Wang1, Qing Shen1, Shuzi Hayase1 (1.The University of Electro-Communications)
Keywords:
perovskite
The tin-based perovskite is currently under active research due to its non-toxic properties compared to lead-based perovskite. However, it exhibits a larger open-circuit voltage loss when using fullerene (C60) as an electron transport layer, attributed to the different energy levels of the conduction and valence bands compared to lead-based perovskite. To mitigate this voltage loss, indene-C60 bisadduct (ICBA) has been employed as an electron transport layer due to its relatively shallow conduction band level. In ICBA devices, the fill factor has always been unsatisfactory. We discovered that the poor fill factor was caused by excess SnI4 on the surface of the perovskite. Substantial improvement in the fill factor of the device was achieved by spin-coating the surface with isopropyl alcohol (IPA) solvent, resulting in a significant enhancement in the device's fill factor and Voc with achieving a 10% photovoltaic conversion efficiency (vs. 3.8% for control). This work reveals that the impurity at the interface is critical for solar cell devices.