English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Organic-inorganic lead halide perovskites containing a mixture of iodide andbromide anions consistently perform better in donor-acceptor heterojunctionsolar cells than the standard methylammonium lead triiodide material. Thisobservation is counterintuitive, as it is generally expected for photovoltaicmaterials that heterogeneities and compositional disorder cause reduced carrierdiffusion length and conversion efficiency. Here, we combine ultrafastphotoinduced electroabsorption and broadband fluorescence up-conversionspectroscopy measurements to scrutinize the carrier dynamics in mixed-cations,mixed-halide lead perovskite thin films. Our results evidence the formation ofcharge transfer excitons (CTE) across the boundaries of domains of varioushalide compositions. A global analysis of photoinduced transient Stark signalsshows that CTE evolve gradually from Br-rich to I-rich domains over tens tohundreds of picoseconds. Rather than constituting recombination centres,boundaries between domains of various halide compositions appear then to favourcharge carrier separation by driving photogenerated holes along channels ofdecreasing bromide content.

Inter-Domain Charge Transfer as a Rationale for Superior Photovoltaic Performances of Mixed Halide Lead Perovskites