摘要
Perovskite crystal facets greatly impact the performance and stability of their corresponding photovoltaic devices.Compared to the(001)facet,the(011)facet yields better photoelectric properties,including higher conductivity and enhanced charge carrier mobility.Thus,achieving(011)facet-exposed films is a promising way to improve device performance.However,the growth of(011)facets is energetically unfavorable in FAPbI_(3) perovskites due to the influence of methylammonium chloride additive.Here,1-butyl-4-methylpyridinium chloride([4MBP]Cl)was used to expose(011)facets.The[4MBP]^(+)cation selectively decreases the surface energy of the(011)facet enabling the growth of the(011)plane.The[4MBP]^(+)cation causes the perovskite nuclei to rotate by 45°such that(011)crystal facets stack along the out-of-plane direction.The(011)facet has excellent charge transport properties and can achieve better-matched energy level alignment.In addition,[4MBP]Cl increases the activation energy barrier for ion migration,suppressing decomposition of the perovskite.As a result,a small-size device(0.06 cm2)and a module(29.0 cm2)based on exposure of the(011)facet achieved power conversion efficiencies of 25.24%and 21.12%,respectively.
基金
This work was funded by the European Union’s Horizon 2020 program,through a FET Proactive research and innovation action under grant agreement No.101084124(DIAMOND)
supported by the 111 Project(B16016),and the Project of Scientific and Technological Support Program in Jiang Su Province(BE2022026-2)
K.Z.thanks to the China Scholarship Council(no.202206730056)
X.F.Z.thanks to the China Scholarship Council(no.202206730058)
R.W.acknowledges the grant(LD22E020002)by the Natural Science Foundation of Zhejiang Province of China.
