Owing to their outstanding optoelectronic properties,all-inorganic CsPbBr_(3) perovskite nanocrystals(NCs)are regarded as excellent materials for various optoelectronic applications.Unfortunately,their practical appli...Owing to their outstanding optoelectronic properties,all-inorganic CsPbBr_(3) 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 CsPbBr_(3)@Cs_(4)PbBr_(6) NCs via tetraoctylammonium bromide ligand induction at room temperature.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6) NCs show a high photoluminescence quantum yield of 94%.In order to prevent Cs4PbBr6 from being converted back to CsPbBr_(3) NCs when exposed to water,a second coating layer of SiO2 is formed on the surface of the CsPbBr_(3)@Cs_(4)PbBr_(6) NCs by the facile hydrolysis of tetramethoxysilane.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2) NCs with their double coating structure have outstanding stability against not only a polar solvent(ethanol)but also water and heat.The as-prepared CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2) 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.展开更多
文摘通过CdBr_(2)对全无机CsPbBr_(3)钙钛矿薄膜进行钝化处理,研究不同浓度CdBr_(2)的异丙醇溶液对全无机CsPbBr_(3)钙钛矿太阳能电池光电性能的影响.结果表明:CdBr_(2)钝化CsPbBr_(3)钙钛矿表面后,降低了钙钛矿表面的Br空位缺陷密度,抑制了非辐射复合,促进了光生电子和空穴的抽取和传输,因此降低了界面光电子复合损失,使全无机钙钛矿太阳能电池器件的光电转换效率从6.58%提高到8.19%,开路电压从1.368 V提高到1.531 V.
基金National Natural Science Foundation of China(11974063,61904023)Key Program Science Foundation of Natural Science Foundation of Chongqing(cstc2020jcyj-jqX0028)Chongqing Special Postdoctoral Science Foundation(cstc2019jcyj-54bsh0026).
文摘Owing to their outstanding optoelectronic properties,all-inorganic CsPbBr_(3) 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 CsPbBr_(3)@Cs_(4)PbBr_(6) NCs via tetraoctylammonium bromide ligand induction at room temperature.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6) NCs show a high photoluminescence quantum yield of 94%.In order to prevent Cs4PbBr6 from being converted back to CsPbBr_(3) NCs when exposed to water,a second coating layer of SiO2 is formed on the surface of the CsPbBr_(3)@Cs_(4)PbBr_(6) NCs by the facile hydrolysis of tetramethoxysilane.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2) NCs with their double coating structure have outstanding stability against not only a polar solvent(ethanol)but also water and heat.The as-prepared CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2) 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.
