Enhancing the charge extraction and stability of perovskite solar cells using strontium titanate (SrTiO3) electron transport layer

by Marios Neophytou, Michele De Bastiani, Nicola Gasparini, Erkan Aydin, Esma Ugur, Akmaral Seitkhan, Floriana Moruzzi, Yasmin Choaie, Alexandra J Ramadan, Joel Troughton, Rawad Hallani, Achilleas Savva, Leonidas Tsetseris, Sahika Inal, Derya Baran, Frédéric Laquai, Thomas D. Anthopoulos, Henry J. Snaith, Stefaan De Wolf, Iain McCulloch
Article Year: 2019

Bibliography

Neophytou, M., De Bastiani, M., Gasparini, N., Aydin E., Ugur, E., Seitkhan, A., Moruzzi, F., Choaie, Y., Ramadan, A. J., Troughton, J., Hallani, R., Savva, A., Tsetseris, L., Inal, S., Baran, D., Laquai, F., Anthopoulos, T., Snaith,  H. J., De Wolf, S., McCulloch, I., Enhancing the charge extraction and stability of perovskite solar cells using strontium titanate (SrTiO3) electron transport layer, ACS Applied Energy Materials 2019, XXXX, (Just accepted)

Abstract

Charge transport layers strongly influence the performance of perovskite solar cells (PSCs). To date, compact layers and mesoporous scaffolds of titanium dioxide have emerged as good electron transport layers (ETL), enabling record power conversion efficiencies (PCE). However, these ETLs require sintering above 400 °C, which excludes them from low-temperature applications such as flexible devices and silicon-heterojunction tandems. Furthermore, the instability of TiO2 under prolonged exposure to sunlight appears to be a critical issue. Here, we present the promising characteristics of low-temperature processed strontium titanate (STO) as an ETL to realize PSCs with 19% PCE. STO is a wide bandgap transparent inorganic perovskite. Compared to other low-temperature processed interlayers, STO reduces the parasitic absorption in the ultraviolet and visible range, improves the electron transport and greatly increases the stability of the devices, retaining ~80% of their initial efficiency after 1000 hours of constant white light illumination.

Keywords

electron-selective contact strontium titanate perovskite solar cells