2 research outputs found
A Universal Grain “Cage” to Suppress Halide Segregation of Mixed-Halide Inorganic Perovskite Solar Cells
Bandgap-tunable mixed-halide perovskites offer exciting
opportunities
to construct efficient multijunction tandem solar cells. However,
the ion migration always causes halide segregation, which inevitably
creates detrimental defects and deteriorates the photovoltaic performances.
Here, we report a universal caging strategy to suppress halide segregation
by in situ formation of conjugated covalent organic frameworks (COFs)
catalyzed by PbX2 (X = Br and I) during the formation of
mixed-halide perovskite. Through theoretical calculation and systematic
investigation, the strong electron-donating feature of COFs is shown
to effectively solidify the soft lattice and impede the iodide ion
transport from bulk to grain boundary, decelerating the light-induced
halide-demixing process. Finally, the nonradiative recombination is
significantly reduced, boosting efficiency up to 11.50% for an inorganic
CsPbIBr2 perovskite solar cell and 14.35% for a CsPbI2Br cell with a prolonged shelf life and an improved photostability
Pd-Catalyzed Three-Component Reaction of Anilines, Ethyl Vinyl Ether, and Nitro-Paraffin: Assembly of β‑Nitroamines
A novel palladium-catalyzed amination
and nitration of ethyl vinyl
ether for the construction of β-nitroamine derivatives under
mild conditions has been developed. This transformation provides a
new strategy for the installation of amino and nitro from aromatic
amines and nitro-paraffin into alkenes. Morpholine resulted in the <i>aza</i>-Henry reaction, while DABCO led to the unexpected rearrangement