Hauptmenü
• Autor
• Aristidou, Nicholas
• Sanchez-Molina, Irene
• Chotchuangchutchaval, Thana
• Brown, Michael
• Martinez, Luis
• Rath, Thomas
• Haque, Saif A.
• TitelThe Role of Oxygen in the Degradation of Methylammonium Lead Trihalide Perovskite Photoactive Layers
• Datei
• DOI10.1002/anie.201503153
• Erschienen inAngewandte Chemie
• Band54
• Erscheinungsjahr2015
• Heft28
• Seiten8208-8212
• Zugriffsrechte
• AbstractIn this paper we report on the influence of light and oxygen on the stability of $$CH_3NH_3PbI_3$$ perovskite-based photoactive layers. When exposed to both light and dry air the $$mp-Al_2O_3/CH_3NH_3PbI_3$$ photoactive layers rapidly decompose yielding methylamine, $$PbI_2$$, and $$I_2$$ as products. We show that this degradation is initiated by the reaction of superoxide $$(O_2^−)$$ with the methylammonium moiety of the perovskite absorber. Fluorescent molecular probe studies indicate that the $$O_2^−$$ species is generated by the reaction of photoexcited electrons in the perovskite and molecular oxygen. We show that the yield of $$O_2^−$$ generation is significantly reduced when the $$mp-Al_2O_3$$ film is replaced with an $$mp-TiO_2$$ electron extraction and transport layer. The present findings suggest that replacing the methylammonium component in $$CH_3NH_3PbI_3$$ to a species without acid protons could improve tolerance to oxygen and enhance stability.