Gaining Insight into the Effect of Organic Interface Layer on Suppressing Ion Migration Induced Interfacial Degradation in Perovskite Solar Cells

Jiaoyi Ning, Yanan Zhu, Zhao Hu, Yuhao Shi, Muhammad Umair Ali, Junpeng He, Yaowu He, Feng Yan, Shihe Yang, Jingsheng Miao, Hong Meng

Research output: Journal article publicationJournal articleAcademic researchpeer-review

8 Citations (Scopus)

Abstract

Ion migration induced interfacial degradation is a detrimental factor for the stability of perovskite solar cells (PSCs) and hence requires special attention to address this issue for the development of efficient PSCs with improved stability. Here, an “S-shaped, hook-like” organic small molecule, naphthalene diimide derivative (NDI-BN), is employed as a cathode interface layer (CIL) to tailor the [6,6]-phenylC61-butyric acid methylester (PCBM)/Ag interface in inverted PSCs. By realizing enhanced electron extraction capability via the incorporation of NDI-BN, a peak power conversion efficiency of 21.32% is achieved. Capacitance–voltage measurements and X-ray photoelectron spectroscopy analysis confirmed an obvious role of this new organic CIL in successfully blocking ionic diffusion pathways toward the Ag cathode, thereby preventing interfacial degradation and improving device stability. The molecular packing motif of NDI-BN further unveils its densely packed structure with π–π stacking force which has the ability to effectually hinder ion migration. Furthermore, theoretical calculations reveal that intercalation of decomposed perovskite species into the NDI clusters is considerably more difficult compared with the PCBM counterparts. This substantial contrast between NDI-BN and PCBM molecules in terms of their structures and packing fashion determines the different tendencies of ion migration and unveils the superior potential of NDI-BN in curtailing interfacial degradation.

Original languageEnglish
Article number2000837
JournalAdvanced Functional Materials
Volume30
Issue number35
Early online date12 Jul 2020
DOIs
Publication statusPublished - 1 Aug 2020

Keywords

  • high-efficiency
  • interfacial degradation
  • organic interface layer
  • perovskite solar cells
  • stability

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

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