Spin coating epitaxial heterodimensional tin perovskites for light-emitting diodes.

Environmentally friendly tin (Sn) perovskites have received considerable attention due to their great potential for replacing their toxic lead counterparts in applications of photovoltaics and light-emitting diodes (LEDs). However, the device performance of Sn perovskites lags far behind that of lead perovskites, and the highest reported external quantum efficiencies of near-infrared Sn perovskite LEDs are below 10%. The poor performance stems mainly from the numerous defects within Sn perovskite crystallites and grain boundaries, leading to serious non-radiative recombination.

Enhanced Charge Balance for Efficient Electroluminescence from Cesium Copper Halides.

Cesium copper halides have the advantages of high photoluminescence quantum efficiency and good stability, making them attractive for replacing toxic lead halides in the field of perovskite light-emitting diodes (LEDs). However, due to their shallow conduction band and the lack of electron transport layers compatible with it, it remains a great challenge to achieve charge balance in LED devices. This drawback manifests as the accumulation of holes at the interface between the emitting layer and electron transport layer, resulting in nonradiative recombination.

Vapor-Assisted In Situ Recrystallization for Efficient Tin-Based Perovskite Light-Emitting Diodes.

Tin-based perovskites are a promising candidates to replace their toxic lead-based counterparts in optoelectronic applications, such as light-emitting diodes (LEDs). However, the development of tin perovskite LEDs is slow due to the challenge of obtaining high-quality tin perovskite films. Here, a vapor-assisted spin-coating method is developed to achieve high-quality tin perovskites and high-efficiency LEDs.

Extremely stable europium-organic framework for luminescent sensing of CrO and Fe in aqueous systems.

Three novel 3D lanthanide-organic frameworks, namely [Ln2L(1,3-bdc)3]·5H2O (Ln: Eu, Sm and Dy), with a 412·63 topology based on a zwitterionic ligand, 4-bis(4-carboxylatopyridinium-1-methylene)benzene dichloride (H2LCl2), and 1,3-benzene dicarboxylic acid (1,3-H2bdc) have been synthesized hydrothermally. Notably, the Ln-MOFs are extremely stable in an aqueous system and are capable of resisting acids or bases over a wide pH range from 3 to 11. Meanwhile, an Eu-MOF is further proven to be a promising dual sensor in an aqueous system toward Cr2O72- and Fe3+.