Nanoparticulate Metal Oxide Top Electrode Interface Modification Improves the Thermal Stability of Inverted Perovskite Photovoltaics

Ioannis T Papadas; Fedros Galatopoulos; Gerasimos S Armatas; Nir Tessler; Stelios A Choulis

doi:10.3390/nano9111616

Nanoparticulate Metal Oxide Top Electrode Interface Modification Improves the Thermal Stability of Inverted Perovskite Photovoltaics

Nanomaterials (Basel). 2019 Nov 14;9(11):1616. doi: 10.3390/nano9111616.

Authors

Ioannis T Papadas¹, Fedros Galatopoulos¹, Gerasimos S Armatas², Nir Tessler³, Stelios A Choulis¹

Affiliations

¹ Molecular Electronics and Photonics Research Unit, Department of Mechanical Engineering and Materials Science and Engineering, Cyprus University of Technology, Limassol 3603, Cyprus.
² Department of Materials Science and Technology, University of Crete, 71003 Heraklion, Greece.
³ Sara and Moshe Zisapel Nano-Electronic Center, Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.

Abstract

Solution processed γ-Fe₂O₃ nanoparticles via the solvothermal colloidal synthesis in conjunction with ligand-exchange method are used for interface modification of the top electrode in inverted perovskite solar cells. In comparison to more conventional top electrodes such as PC(70)BM/Al and PC(70)BM/AZO/Al, we show that incorporation of a γ-Fe₂O₃ provides an alternative solution processed top electrode (PC(70)BM/γ-Fe₂O₃/Al) that not only results in comparable power conversion efficiencies but also improved thermal stability of inverted perovskite photovoltaics. The origin of improved stability of inverted perovskite solar cells incorporating PC(70)BM/ γ-Fe₂O₃/Al under accelerated heat lifetime conditions is attributed to the acidic surface nature of γ-Fe₂O₃ and reduced charge trapped density within PC(70)BM/ γ-Fe₂O₃/Al top electrode interfaces.

Keywords: accelerated lifetime; charge traps density; degradation mechanisms; electrodes; impedance spectroscopy; interfaces; inverted perovskites solar cells; nanoparticulate metal oxides; thermal stability.

Grants and funding

647311/H2020 European Research Council