Dissolved-Cl<sub>2</sub> triggered redox reaction enables high-performance perovskite solar cells.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37349332.
- Also identified by DOI 10.1038/s41467-023-39260-4 and PMC identifier 10287705.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Constructing 2D/3D perovskite heterojunctions is effective for the surface passivation of perovskite solar cells (PSCs). However, previous reports that studying perovskite post-treatment only physically deposits 2D perovskite on the 3D perovskite, and the bulk 3D perovskite remains defective. Herein, we propose Cl<sub>2</sub>-dissolved chloroform as a multifunctional solvent for concurrently constructing 2D/3D perovskite heterojunction and inducing the secondary growth of the bulk grains. The mechanism of how Cl<sub>2</sub> affects the performance of PSCs is clarified. Specifically, the dissolved Cl<sub>2</sub> reacts with the 3D perovskite, leading to Cl/I ionic exchange and Ostwald ripening of the bulk grains. The generated Cl<sup>-</sup> further diffuses to passivate the bulk crystal and buried interface of PSCs. Hexylammonium bromide dissolved in the solvent reacts with the residual PbI<sub>2</sub> to form 2D/3D heterojunctions on the surface. As a result, we achieved high-performance PSCs with a champion efficiency of 24.21% and substantially improved thermal, ambient, and operational stability.
Medical subject headings
- Oxides
- Calcium Compounds