Tailoring Perovskite Adjacent Interfaces by Conjugated Polyelectrolyte for Stable and Efficient Solar Cells. Issue 5 (25th February 2020)

• Record Type: Journal Article
• Authors: Li, Bowei; Xiang, Yuren; Jayawardena, K. D. G. Imalka; Luo, Deying; Watts, John F.; Hinder, Steven; Li, Hui; Ferguson, Victoria; Luo, Haitian; Zhu, Rui; Silva, S. Ravi P.; Zhang, Wei
• Is Part Of: Solar RRL. Volume 4:Issue 5(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-25
• Subjects: conjugated polyelectrolytes -- interface engineering -- nonradiative recombination -- perovskite solar cells; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202000060
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Interface engineering is an effective means to enhance the performance of thin‐film devices, such as perovskite solar cells (PSCs). Herein, a conjugated polyelectrolyte, poly[(9, 9‐bis(3′‐(( N, N ‐dimethyl)‐ N ‐ethyl‐ammonium)‐propyl)‐2, 7‐fluorene)‐alt‐2, 7‐(9, 9‐dioctylfluorene)]di‐iodide (PFN‐I), is used at the interfaces between the hole transport layer (HTL)/perovskite and perovskite/electron transport layer simultaneously, to enhance the device power conversion efficiency (PCE) and stability. The fabricated PSCs with an inverted planar heterojunction structure show improved open‐circuit voltage ( V oc ), short‐circuit current density ( J sc ), and fill factor, resulting in PCEs up to 20.56%. The devices maintain over 80% of their initial PCEs after 800 h of exposure to a relative humidity 35–55% at room temperature. All of these improvements are attributed to the functional PFN‐I layers as they provide favorable interface contact and defect reduction. Abstract : A conjugated polyelectrolyte is used for simultaneously tailoring the perovskite adjacent interfaces. Herein, for the first time, poly[(9, 9‐bis(3′‐(( N, N ‐dimethyl)‐ N ‐ethyl‐ammonium)‐propyl)‐2, 7‐fluorene)‐alt‐2, 7‐(9, 9‐dioctylfluorene)]di‐iodide (PFN‐I)is exploited in inverted planar perovskite solar cells. At the hole transport layer/perovskite interface, the PFN‐I is beneficial for solving the dewetting issue. At the perovskite/electron transport layer interface, the PFN‐I is advantageous for passivating defects.