A-site cation influence on the conduction band of lead bromide perovskitesShow others and affiliations
2022 (English)In: Nature Communications, E-ISSN 2041-1723, Vol. 13, no 1, article id 3839Article in journal (Refereed) Published
Abstract [en]
Hot carrier solar cells hold promise for exceeding the Shockley-Queisser limit. Slow hot carrier cooling is one of the most intriguing properties of lead halide perovskites and distinguishes this class of materials from competing materials used in solar cells. Here we use the element selectivity of high-resolution X-ray spectroscopy and density functional theory to uncover a previously hidden feature in the conduction band states, the sigma-pi energy splitting, and find that it is strongly influenced by the strength of electronic coupling between the A-cation and bromide-lead sublattice. Our finding provides an alternative mechanism to the commonly discussed polaronic screening and hot phonon bottleneck carrier cooling mechanisms. Our work emphasizes the optoelectronic role of the A-cation, provides a comprehensive view of A-cation effects in the crystal and electronic structures, and outlines a broadly applicable spectroscopic approach for assessing the impact of chemical alterations of the A-cation on perovskite electronic structure. The A-cation influence on the mechanism of slow hot carrier cooling in perovskites is controversial. Here, Man et al. resolve a debated issue regarding A-cation influence on the electronic structure of lead halide perovskites.
Place, publisher, year, edition, pages
Nature Research , 2022. Vol. 13, no 1, article id 3839
National Category
Energy Engineering
Identifiers
URN: urn:nbn:se:kth:diva-315844DOI: 10.1038/s41467-022-31416-yISI: 000820771400022PubMedID: 35787623Scopus ID: 2-s2.0-85133271664OAI: oai:DiVA.org:kth-315844DiVA, id: diva2:1684118
Note
QC 20220721
2022-07-212022-07-212024-03-18Bibliographically approved