In-Situ Growth of One-Dimensional Blocking Layer to Mitigate Deficient Surface of Single-Crystal Perovskites.

Organic-inorganic halide perovskite (OIHP) single crystals are promising for optoelectronic application, but their high surface trap density and associated ion migration hinders device performance and stability. Herein, a one-dimensional (1D) perovskites are designed and proposed as blocking layer at the crystal/electrode interface to mitigate the surface issues. As a model system, the interface ion migration in CsFAPbI (FA=formamidinium) single-crystal perovskite solar cells (PSCs) is obviously suppressed, leading to increase of T lifetime from 260 to 1000 hours, five times better than previously reported results.

Perovskite Single Crystals with Self-Cleaning Surface for Efficient Photovoltaics.

Metal halide perovskite single crystals are promising for diverse optoelectronic applications. As a universal issue of solution-grown perovskite single crystals, surface contamination causes adverse effect on material properties and device performance. Herein, learning from the self-cleaning effect of lotus leaf, we address the surface contamination issue by introducing an amphiphilic long-chain organic amine into the perovskite crystal growth solution.

High-Performance and Self-Powered X-Ray Detectors Made of Smooth Perovskite Microcrystalline Films with 100 μm Grains.

Perovskite single crystals and polycrystalline films have complementary merits and deficiencies in X-ray detection and imaging. Herein, we report preparation of dense and smooth perovskite microcrystalline films with both merits of single crystals and polycrystalline films through polycrystal-induced growth and hot-pressing treatment (HPT). Utilizing polycrystalline films as seeds, multi-inch-sized microcrystalline films can be in situ grown on diverse substrates with maximum grain size reaching 100 μm, which endows the microcrystalline films with comparable carrier mobility-lifetime (μτ) product as single crystals.

Solution-Grown Chloride Perovskite Crystal of Red Afterglow.

We report the growth of a halide-based double perovskite, Cs Na Ag InCl :y%Mn, via a facile hydrothermal reaction at 180 °C. Through a co-doping strategy of both Na and Mn , the as-prepared crystals exhibited a red afterglow featuring a high color purity (ca. 100 %) and a long duration time (>5400 s), three orders of magnitude longer than those solution-processed organic afterglow crystals.

Excitation Management of Lead-Free Perovskite Nanocrystals Through Doping.

Despite their low toxicity and phase stability, lead-free double perovskite nanocrystals, CsAgInCl in specific, have suffered from low quantum yield of photoluminescence. This is mainly due to two reasons, including (i) the quenching effect from metal silver which was usually formed at high temperature from Ag reduction in the presence of organic amines and (ii) the parity-forbidden transition of pristine double perovskites. Here, we reported a room-temperature synthesis of CsAgInCl nanocrystals in an inverse microemulsion system, where Ag reduction was largely suppressed.