Charge Transfer Dynamics between Carbon Nanotubes and Hybrid Organic Metal Halide Perovskite Films

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• 作者：Philip Schulz ; Anne-Marie Dowgiallo ; Mengjin Yang ; Kai Zhu ; Jeffrey L. Blackburn ; Joseph J. Berry
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2016
• 出版时间：February 4, 2016
• 年：2016
• 卷：7
• 期：3
• 页码：418-425
• 全文大小：462K
• ISSN：1948-7185

文摘

In spite of the rapid rise of metal organic halide perovskites for next-generation solar cells, little quantitative information on the electronic structure of interfaces of these materials is available. The present study characterizes the electronic structure of interfaces between semiconducting single walled carbon nanotube (SWCNT) contacts and a prototypical methylammonium lead iodide (MAPbI₃) absorber layer. Using photoemission spectroscopy we provide quantitative values for the energy levels at the interface and observe the formation of an interfacial dipole between SWCNTs and perovskite. This process can be ascribed to electron donation from the MAPbI₃ to the adjacent SWCNT making the nanotube film n-type at the interface and inducing band bending throughout the SWCNT layer. We then use transient absorbance spectroscopy to correlate this electronic alignment with rapid and efficient photoexcited charge transfer. The results indicate that SWCNT transport and contact layers facilitate rapid charge extraction and suggest avenues for enhancing device performance.