RbPbI3 Seed Embedding in PbI2 Substrate Tailors the Facet Orientation and Crystallization Kinetics of Perovskites

Small. 2024 Mar;20(11):e2307219. doi: 10.1002/smll.202307219. Epub 2023 Oct 26.

Abstract

High power conversion efficiencies (PCEs) in perovskite solar cells (PSCs) have always been awe-inspiring, but perovskite films scalability is an exacting precondition for PSCs commercial deployment, generally unachievable through the antisolvent technique. On the contrary, in the two-step sequential method, the perovskite's uncontrolled crystallization and unnecessary PbI2 residue impede the device's performance. These two issues motivated to empower the PbI2 substrate with orthorhombic RbPbI3 crystal seeds, which act as grown nuclei and develop orientated perovskites lattice stacks, improving the perovskite films morphologically and reducing the PbI2 content in eventual perovskite films. Thence, achieving a PCE of 24.17% with suppressed voltage losses and an impressive life span of 1140 h in the open air.

Keywords: nucleation growth; perovskite seeds; perovskite solar cells; two-step sequential method.