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Understanding carrier recombination processes in metal halide perovskites is fundamentally important to further improving the efficiency of perovskite solar cells, yet the accurate recombination velocity at grain boundaries (GBs) has not been determined. Here, we report the determination of carrier recombination velocities at GBs (SGB) of polycrystalline perovskites by mapping the transient photoluminescence pattern change induced by the nonradiative recombination of carriers at GBs. Charge recombination at GBs is revealed to be even stronger than at surfaces of unpassivated films, with averageSGBreaching 2200 to 3300 cm/s. Regular surface treatments do not passivate GBs because of the absence of contact at GBs. We find a surface treatment using tributyl(methyl)phosphonium dimethyl phosphate that can penetrate into GBs by partially dissolving GBs and converting it into one-dimensional perovskites. It reduces the averageSGBby four times, with the lowestSGBof 410 cm/s, which is comparable to surface recombination velocities after passivation.
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Modeling the subsurface adsorption of atomic oxygen in silver from high vacuum to high pressure
Using anab initio, three-dimensional lattice-gas model in combination with Monte Carlo simulations, we determine the coverages, pressures, and temperatures at which oxygen atoms adsorb on the surface and in the subsurface of a silver surface.
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- Award ID(s):
- 1753273
- PAR ID:
- 10656978
- Publisher / Repository:
- Physical Chemistry Chemical Physics
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 27
- Issue:
- 15
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 7816 to 7825
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/D5CP00009B
