Facile synthesis of composite tin oxide nanostructures for high-performance planar perovskite solar cells

Mriganka Singh, Annie Ng, Zhiwei Ren, Hanlin Hu, Hong Cheu Lin, Chih Wei Chu, Gang Li

Research output: Journal article publicationJournal articleAcademic researchpeer-review

36 Citations (Scopus)

Abstract

Metal oxide carrier transporting layers have been investigated widely in organic/inorganic lead halide perovskite solar cells (PSCs). Tin oxide (SnO 2 ) is a promising alternative to the titanium dioxide commonly used in the electron transporting layer (ETL), due to its tunable carrier concentration, high electron mobility, amenability to low-temperature annealing processing, and large energy bandgap. In this study, a facile method was developed for the preparation of a room-temperature-processed SnO 2 electron transporting material that provided a high-quality ETL, leading to PSCs displaying high power conversion efficiency (PCE) and stability. A novel physical ball milling method was first employed to prepare chemically pure ground SnO 2 nanoparticles (G-SnO 2 ), and a sol–gel process was used to prepare a compact SnO 2 (C-SnO 2 ) layer. The effects of various types of ETLs (C-SnO 2 , G-SnO 2 , composite G-SnO 2 /C-SnO 2 ) on the performance of the PSCs are investigated. The composite SnO 2 nanostructure formed a robust ETL having efficient carrier transport properties; accordingly, carrier recombination between the ETL and mixed perovskite was inhibited. PSCs incorporating C-SnO 2 , G-SnO 2 , and G-SnO 2 /C-SnO 2 as ETLs provided PCEs of 16.46, 17.92, and 21.09%, respectively. In addition to their high efficiency, the devices featuring the composite SnO 2 (G-SnO 2 /C-SnO 2 ) nanostructures possessed excellent long-term stability—they maintained 89% (with encapsulation) and 83% (without encapsulation) of their initial PCEs after 105 days (>2500 h) and 60 days (>1400 h), respectively, when stored under dry ambient air (20 ± 5 RH %).

Original languageEnglish
Pages (from-to)275-284
Number of pages10
JournalNano Energy
Volume60
DOIs
Publication statusPublished - Jun 2019

Keywords

  • Ball-milling
  • Composite nanostructure
  • Electron transport layer
  • Perovskite solar cells
  • Tin oxide

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)
  • Electrical and Electronic Engineering

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