Ligand-bridged charge extraction and enhanced quantum efficiency enable efficient n–i–p perovskite/silicon tandem solar cells

by Erkan Aydin, Jiang Liu, Esma Ugur, Randi Azmi, George T. Harrison, Yi Hou, Bin Chen, Shynggys Zhumagali, Michele De Bastiani, Mingcong Wang, Waseem Raja, Thomas G. Allen, Atteq ur Rehman, Anand S. Subbiah, Maxime Babics, Aslihan Babayigit, Furkan H. Isikgor, Kai Wang, Emmanuel Van Kerschaver, Leonidas Tsetseris, Edward H. Sargent, Frédéric Laquai, Stefaan De Wolf
Article Year: 2021 DOI:


Aydin, E., Liu, J., Ugur, E., Azmi, R., T. Harrison, G., Hou, Yi., Chen, B., Zhumagali, S., De Bastiani, M., Wang, M., Raja, W., G. Allen, T., Rehman, A., S. Subbiah, A., Babics, M., Babayigit, A., H. Isikgor. F., Wang, K., Van Kerschaver, E., Tsetseris, L., H. Sargent, E., Laquai, F., De Wolf, S. 

Extra Information

This study demonstrates 27%-efficient perovskite/silicon tandem solar cells in n–i–p configuration by developing novel electron and hole selective contacts, which combine high broadband transparency with efficient charge extraction. This study took place in the June issue of Energy & Environmental Science.


Translating the high power conversion efficiencies of single-junction perovskite solar cells in their classic, non-inverted (n–i–p) architecture to efficient monolithic n–i–p perovskite/silicon tandem solar cells with high current densities has been a persistent challenge due to the lack of low-temperature processable, chemically-insoluble contact materials with appropriate polarity and sufficient optical transparency. To address this, we developed sputtered amorphous niobium oxide (a-NbOx) with ligand-bridged C60 as an efficient electron-selective contact, deposited on the textured-silicon bottom cell. For the sunward, hole-selective contact we implemented a stack of molecularly doped broadband transparent evaporated 2,2′,7,7′-tetra(N,N-di-p-tolyl)amino-9,9-spirobifluorene (spiro-TTB) and atomic layer deposited vanadium oxide, which further enhances the device quantum efficiency. Combining these contact materials with two-dimensional perovskite passivation on the micrometer-thick solution-processed perovskite top cell yields 27% efficient monolithic n–i–p perovskite/silicon tandem solar cells, which represents one of the highest power conversion efficiencies reported on pyramidal textured crystalline silicon bottom cells, and the highest with this polarity.


Perovskite/silicon tandem solar cells flipped polarity n-i-p tandems niobium oxide vanadium oxide spiro-TTB textured interfaces champion solar cells C60-SAM Two-dimensional passivation enhanced stability