Simplified Fabrication for High-Performance CsPbIBr2 Perovskite Solar Cells via Nanoparticle Centrifugal Deposition

The hot injection method is a commonly employed technique for the synthesis of perovskite nanoparticles that are subsequently used in the fabrication of perovskite solar cells (PSCs). However, this method presents a significant challenge related to the removal of ligands and the purification of nanoparticles. The issue arises from the use of long-chain ligands that are crucial for stabilizing the nanoparticles during their synthesis. These long-chain ligands, while serving their purpose during nanoparticle formation, can pose hindrances when the nanoparticles are integrated into a solar cell. Here, we prepared CsPbIBr2 nanoparticles stabilized with a short-chain ligand, amylamine (C5H13N). These nanoparticles were used to create nanoparticle films without the need for additional cleaning and purification steps. Subsequently, a high-quality bulk film was obtained by heat treatment. Additionally, we introduced a fast dual-step centrifugal deposition method differing from the conventional layer-to-layer spin coating approach. Films produced using this dual-step centrifugal deposition method exhibited a grain size of approximately 220 nm and near-vertical growth. As a result, our perovskite solar cells achieved a superior power conversion efficiency (PCE) exceeding 7.1%. This simplified and expeditious fabrication method holds promising implications for streamlining the perovskite solar cell production process in the future.