由于其出色的光电性能,全无机 CsPbBr3 钙钛矿纳米晶体 (NCs) 被认为是各种光电应用的优秀材料。不幸的是,它们的实际应用受到对水、热和极性溶剂的稳定性差的限制。在这里,我们提出了一种在室温下通过四辛基溴化铵配体诱导CsPbBr3@Cs4PbBr6 NCs 的简单合成策略。所得CsPbBr3@Cs4PbBr6 NC 显示出 94% 的高光致发光量子产率。为了防止 Cs4PbBr6 在暴露于水中时转化回 CsPbBr3 NCs,通过四甲氧基硅烷的简单水解,在 CsPbBr3@Cs4PbBr6 NCs 的表面形成 SiO2 的第二层涂层。所得的 CsPbBr3@Cs4PbBr6/SiO2 NC 具有双重涂层结构,不仅对极性溶剂(乙醇)具有出色的稳定性,而且对水和热也具有出色的稳定性。所制备的 CsPbBr3@Cs4PbBr6/SiO2 NC 在高效白光发光二极管 (WLED) 中用作绿光发射器,显色指数 (CRI) 高达 91,功率效率高达 59.87 lm W−1。此外,在可见光通信 (VLC) 中使用这些 WLED 的最大速率为 44.53 Mbps,这表明所报道的方法和材料在固态照明和 VLC 方面具有巨大潜力。
"点击查看英文标题和摘要"
High-performance CsPbBr3@Cs4PbBr6/SiO2 nanocrystals via double coating layers for white light emission and visible light communication
Owing to their outstanding optoelectronic properties, all-inorganic CsPbBr3 perovskite nanocrystals (NCs) are regarded as excellent materials for various optoelectronic applications. Unfortunately, their practical applications are limited by poor stability against water, heat, and polar solvents. Here, we propose a facile synthesis strategy for CsPbBr3@Cs4PbBr6 NCs via tetraoctylammonium bromide ligand induction at room temperature. The resulting CsPbBr3@Cs4PbBr6 NCs show a high photoluminescence quantum yield of 94%. In order to prevent Cs4PbBr6 from being converted back to CsPbBr3 NCs when exposed to water, a second coating layer of SiO2 is formed on the surface of the CsPbBr3@Cs4PbBr6 NCs by the facile hydrolysis of tetramethoxysilane. The resulting CsPbBr3@Cs4PbBr6/SiO2 NCs with their double coating structure have outstanding stability against not only a polar solvent (ethanol) but also water and heat. The as-prepared CsPbBr3@Cs4PbBr6/SiO2 NCs serve as green emitters in efficient white light-emitting diodes (WLEDs) with a high color rendering index (CRI) of 91 and a high power efficiency 59.87 lm W−1. Furthermore, the use of these WLEDs in visible light communication (VLC) results in a maximum rate of 44.53 Mbps, suggesting the great potential of the reported methods and materials for solid-state illumination and VLC.