Published October 2023 | Version v1
Journal article Open

In-situ SnSe deposition as passivation for scalable and stable quasi-2D lead-tin perovskite solar cells

Authors/Creators

Description

Lead-tin (Pb-Sn) perovskites are a highly promising composition for single-junction and all-perovskite tandem solar cells due to their narrower bandgap and reduced toxicity. While the use of quasi-two-dimensional (quasi-2D) Ruddlesden-Popper phases has resulted in superior stability towards the environment and large improvement in the crystallization with respect to the 3D compositions, very little work has been done towards their deposition with scalable techniques. Here, PEA2(FA0.5MA0.5)4(Pb0.5Sn0.5)5I16 (n=5) with a gradient structure is successfully prepared for the first time by a two-step blade coating. Perovskite films which are treated with tin (II) acetate (SnAc2) along with N, N-dimethylselenourea (DMS) exhibit a reduced number of surface traps and enhanced surface crystallization, owing to the in-situ formation of tin selenide (SnSe). Record devices with power conversion efficiency (PCE) of 15.06%, an open circuit voltage (VOC) of 0.855 V, and negligible hysteresis are obtained. More importantly, the hydrophobic SnSe significantly protects the active layer from the environment. These devices retain 91% of the original PCE after 10 days in ambient air (30%-40% humidity) without encapsulation, and nearly no-degradation of the PCE is detected after over a month of storage in inert atmosphere, and under continuous MPP tracking for 15 hours.

 

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In-situ SnSe deposition as passivation for scalable and stable quasi-2D lead-tin perovskite solar cells_Manuscript.pdf

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Additional details

Funding

European Commission
DIAMOND - Ultra-stable, highly efficient, low-cost perovskite photovoltaics with minimised environmental impact 101084124
National Natural Science Foundation of China
62205264 62205264
Xi'an Jiaotong University
Young Talents Support Program 11302291010704

Dates

Available
2023-10