Heterojunction modification for highly efficient organic-inorganic perovskite solar cells

Konrad Wojciechowski, Samuel D. Stranks, Antonio Abate, Golnaz Sadoughi, Aditya Sadhanala, Nikos Kopidakis, Gary Rumbles, Chang Zhi Li, Richard H. Friend, Alex K Y Jen, Henry J. Snaith

Research output: Contribution to journalArticle

370 Citations (Scopus)

Abstract

Organic-inorganic perovskites, such as CH3NH3PbX3 (X = I, Br, Cl), have emerged as attractive absorber materials for the fabrication of low cost high efficiency solar cells. Over the last 3 years, there has been an exceptional rise in power conversion efficiencies (PCEs), demonstrating the outstanding potential of these perovskite materials. However, in most device architectures, including the simplest thin-film planar structure, a current-voltage response displays an "anomalous hysteresis", whereby the power output of the cell varies with measurement time, direction and light exposure or bias history. Here we provide insight into the physical processes occurring at the interface between the n-type charge collection layer and the perovskite absorber. Through spectroscopic measurements, we find that electron transfer from the perovskite to the TiO2 in the standard planar junction cells is very slow. By modifying the n-type contact with a self-Assembled fullerene monolayer, electron transfer is "switched on", and both the n-type and p-type heterojunctions with the perovskite are active in driving the photovoltaic operation. The fullerene-modified devices achieve up to 17.3% power conversion efficiency with significantly reduced hysteresis, and stabilized power output reaching 15.7% in the planar p-i-n heterojunction solar cells measured under simulated AM 1.5 sunlight.

Original languageEnglish
Pages (from-to)12701-12709
Number of pages9
JournalACS Nano
Volume8
Issue number12
DOIs
Publication statusPublished - Dec 23 2014

Fingerprint

Perovskite
Heterojunctions
heterojunctions
solar cells
Fullerenes
fullerenes
electron transfer
hysteresis
Conversion efficiency
absorbers (materials)
Hysteresis
Solar cells
output
planar structures
sunlight
perovskites
cells
Electrons
absorbers
Time measurement

Keywords

  • fullerene
  • microwave conductivity
  • passivation
  • perovskite
  • photothermal deflection spectroscopy
  • self-Assembled monolayer
  • traps

ASJC Scopus subject areas

  • Engineering(all)
  • Materials Science(all)
  • Physics and Astronomy(all)

Cite this

Wojciechowski, K., Stranks, S. D., Abate, A., Sadoughi, G., Sadhanala, A., Kopidakis, N., ... Snaith, H. J. (2014). Heterojunction modification for highly efficient organic-inorganic perovskite solar cells. ACS Nano, 8(12), 12701-12709. https://doi.org/10.1021/nn505723h

Heterojunction modification for highly efficient organic-inorganic perovskite solar cells. / Wojciechowski, Konrad; Stranks, Samuel D.; Abate, Antonio; Sadoughi, Golnaz; Sadhanala, Aditya; Kopidakis, Nikos; Rumbles, Gary; Li, Chang Zhi; Friend, Richard H.; Jen, Alex K Y; Snaith, Henry J.

In: ACS Nano, Vol. 8, No. 12, 23.12.2014, p. 12701-12709.

Research output: Contribution to journalArticle

Wojciechowski, K, Stranks, SD, Abate, A, Sadoughi, G, Sadhanala, A, Kopidakis, N, Rumbles, G, Li, CZ, Friend, RH, Jen, AKY & Snaith, HJ 2014, 'Heterojunction modification for highly efficient organic-inorganic perovskite solar cells', ACS Nano, vol. 8, no. 12, pp. 12701-12709. https://doi.org/10.1021/nn505723h
Wojciechowski K, Stranks SD, Abate A, Sadoughi G, Sadhanala A, Kopidakis N et al. Heterojunction modification for highly efficient organic-inorganic perovskite solar cells. ACS Nano. 2014 Dec 23;8(12):12701-12709. https://doi.org/10.1021/nn505723h
Wojciechowski, Konrad ; Stranks, Samuel D. ; Abate, Antonio ; Sadoughi, Golnaz ; Sadhanala, Aditya ; Kopidakis, Nikos ; Rumbles, Gary ; Li, Chang Zhi ; Friend, Richard H. ; Jen, Alex K Y ; Snaith, Henry J. / Heterojunction modification for highly efficient organic-inorganic perovskite solar cells. In: ACS Nano. 2014 ; Vol. 8, No. 12. pp. 12701-12709.
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