The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Aboma Mendasa, MSc, PhD. Photo.

Aboma Merdasa

Researcher

Aboma Mendasa, MSc, PhD. Photo.

Alkali Salts as Interface Modifiers in n-i-p Hybrid Perovskite Solar Cells

Author

  • Janardan Dagar
  • Katrin Hirselandt
  • Aboma Merdasa
  • Aniela Czudek
  • Rahim Munir
  • Fengshuo Zu
  • Norbert Koch
  • Thomas Dittrich
  • Eva L. Unger

Summary, in English

After demonstration of a 23% power conversion efficiency, a high operational stability is the next most important scientific and technological challenge in perovskite solar cells (PSCs). A potential failure mechanism is tied to a bias-induced ion migration, which causes current–voltage hysteresis and a decay in the device performance over time. Herein, alkali salts are shown to mitigate hysteresis and stabilize device performance in n-i-p hybrid planar PSCs. Different alkali salts of potassium chloride, iodide, and nitrate as well as sodium chloride and iodide are deposited from aqueous solution onto the n-type contact, based on SnO2, prior to deposition of the perovskite absorber Cs0.05(FA0.83MA0.17)0.95Pb(I0.83Br0.17)3. Introduction of potassium-based alkali salts suppresses the current–voltage hysteresis and stabilizes the operational device stability at the maximum power point. This is attributed to the suppression of hole trapping at the n-type selective transport layer (SnO2)/perovskite interface observed by surface photovoltage spectroscopy, which is interpreted to reduce interfacial recombination and improve charge carrier extraction. The best and most stable performance of 19% is achieved using potassium nitrate as the interface modifier. Devices with higher and more stable performance exhibit substantially lower current transients, analyzed during maximum power point tracking.

Department/s

  • Chemical Physics
  • NanoLund: Centre for Nanoscience

Publishing year

2019-09

Language

English

Publication/Series

Solar RRL

Volume

3

Issue

9

Document type

Journal article

Publisher

Wiley-Blackwell

Topic

  • Materials Chemistry

Keywords

  • alkali salts
  • interface modification
  • n-i-p devices
  • perovskite solar cells

Status

Published

ISBN/ISSN/Other

  • ISSN: 2367-198X