Homogenizing out-of-plane cation composition in perovskite solar cells.

Authors :: Liang Z
Zhang Y
Xu H
Chen W
Liu B
Zhang J
Zhang H
Wang Z
Kang DH
Zeng J
Gao X
Wang Q
Hu H
Zhou H
Cai X
Tian X
Reiss P
Xu B
Kirchartz T
Xiao Z
Dai S
Park NG
Ye J
Pan X
Source :: Nature [Nature] 2023 Dec; Vol. 624 (7992), pp. 557-563. Date of Electronic Publication: 2023 Nov 01.
Publication Year :: 2023
Abstract: Perovskite solar cells with the formula FA <subscript>1-x</subscript> Cs <subscript>x</subscript> PbI <subscript>3</subscript> , where FA is formamidinium, provide an attractive option for integrating high efficiency, durable stability and compatibility with scaled-up fabrication. Despite the incorporation of Cs cations, which could potentially enable a perfect perovskite lattice <superscript>1,2</superscript> , the compositional inhomogeneity caused by A-site cation segregation is likely to be detrimental to the photovoltaic performance of the solar cells <superscript>3,4</superscript> . Here we visualized the out-of-plane compositional inhomogeneity along the vertical direction across perovskite films and identified the underlying reasons for the inhomogeneity and its potential impact for devices. We devised a strategy using 1-(phenylsulfonyl)pyrrole to homogenize the distribution of cation composition in perovskite films. The resultant p-i-n devices yielded a certified steady-state photon-to-electron conversion efficiency of 25.2% and durable stability.<br /> (© 2023. The Author(s).)