Publication
Effective passivation and stabilization of both the inside and interface of a perovskite layer are crucial for perovskite solar cells (PSCs), in terms of efficiency, reproducibility, and stability. Here, the first formamidinium lead iodide (δ-FAPbI3) polymorph passivated and stabilized MAPbI3 PSCs are reported. This novel MAPbI3/δ-FAPbI3 structure is realized via treating a mixed organic cation MA x FA1- x PbI3 perovskite film with methylamine (MA) gas. In addition to the morphology healing, MA gas can also induce the formation of δ-FAPbI3 phase within the perovskite film. The in situ formed 1D δ-FAPbI3 polymorph behaves like an organic scaffold that can passivate the trap state, tunnel contact, and restrict organic-cation diffusion. As a result, the device efficiency is easily boosted to 21%. Furthermore, the stability of the MAPbI3/δ-FAPbI3 film is also obviously improved. This δ-FAPbI3 phase passivation strategy opens up a new direction of perovskite structure modification for further improving stability without sacrificing efficiency.
Paul Joseph Dyson, Ursula Röthlisberger, Felix Thomas Eickemeyer, Lukas Pfeifer, Virginia Carnevali, Nikolaos Lempesis, Lorenzo Agosta, Masaud Hassan S Almalki, Haizhou Lu, Yeonju Kim, Jaeki Jeong
Mounir Driss Mensi, Masaud Hassan S Almalki, Anwar Qasem M Alanazi
Shaik Mohammed Zakeeruddin, Aïcha Hessler-Wyser, Felix Thomas Eickemeyer, Lukas Pfeifer, Christian Michael Wolff, Rita Therisod, Mostafa Rabie Shlaly Bahr Othman, Hong Zhang, Masaud Hassan S Almalki, Anwar Qasem M Alanazi