Presentation Information
[10p-S201-10]Grain Surface Passivation for Efficient and Stable Inorganic Ultrawide-Bandgap Perovskite Solar Cells
〇(DC)Siliang Cao1,2, Md. Abdul Karim1, Md. Emrul Kayesh1, Takeaki Sakurai2, Ashraful Islam1 (1.NIMS, 2.Univ. of Tsukuba)
Keywords:
Inorganic perovskite solar cells,Wide-bandgap perovskite solar cells,Surface passivation
All-perovskite tandem solar cells have made remarkable progress due to their tunable bandgap without quality loss1. Among them, all-inorganic CsPbI3−xBrx perovskite absorbers, which can simply modify the bandgap via adjusting the proportion of iodine (I) and bromine (Br), hold the promise for constructing integrated tandem solar cells in perovskite photovoltaics2. However, until now, the efficiency and operational stability of all-inorganic perovskites still lag behind their hybrid organic-inorganic counterparts, particularly in wide-bandgap (>1.65 eV) I/Br mixed compositions. This limitation primarily arises from the huge energetic mismatch and light-induced phase segregation3. For multiple junction tandem use, the required bandgap above 1.90 eV makes it more challenging to minimize voltage loss caused by non-radiative recombination.
Herein, we have reported a simple fabrication method for inverted 2.1 eV inorganic perovskite solar cells4. Building upon our previous work, we accordingly developed a grain surface passivator at the interface between CsPbIBr2 perovskite and PCBM, which effectively modulated the energetic mismatch and further mitigated the interfacial recombination. The optimized perovskite film exhibited homogeneous and hydrophobic surface, offering a favorable contact to facilitate electron extraction. Additionally, it may form dense bindings to interfacial defect sites and inhibit ion migration, leading to improved phase stability. As a result, we achieved a champion power conversion efficiency of 11.3% with negligible hysteresis. This work reveals a key strategy for addressing energetic mismatch and interface modulation in ultrawide-bandgap perovskite solar cells.
Herein, we have reported a simple fabrication method for inverted 2.1 eV inorganic perovskite solar cells4. Building upon our previous work, we accordingly developed a grain surface passivator at the interface between CsPbIBr2 perovskite and PCBM, which effectively modulated the energetic mismatch and further mitigated the interfacial recombination. The optimized perovskite film exhibited homogeneous and hydrophobic surface, offering a favorable contact to facilitate electron extraction. Additionally, it may form dense bindings to interfacial defect sites and inhibit ion migration, leading to improved phase stability. As a result, we achieved a champion power conversion efficiency of 11.3% with negligible hysteresis. This work reveals a key strategy for addressing energetic mismatch and interface modulation in ultrawide-bandgap perovskite solar cells.