Volatile eutectics to tailor crystallization for perovskite optoelectronics.

Volatile eutectic treatment with zinc bromide and methylammonium chloride enhances perovskite solar cell efficiency to 26.5% PCE in laboratory devices.

• Why it matters: Improving radiative efficiency of halide perovskite films is crucial to reaching fundamental solar cell performance limits, but current methods lack precise control over crystallization and defect reduction.
• What they did: The study used eutectic interactions between zinc bromide and methylammonium chloride additives to tailor perovskite crystallization, analyzed with nanoprobe x-ray microscopy and tested in solar cells and modules.
• The result: This approach yielded high photoluminescence, reduced defect density, and achieved certified 25.9% PCE in small-area cells and 23.9% in large modules, also enabling 26.1% external quantum efficiency in LEDs.