Graduate School at Shenzhen , Tsinghua University , Shenzhen 518055 , China.
School of Photovoltaic and Renewable Energy Engineering , University of New South Wales , Sydney 2052 , Australia.
ACS Appl Mater Interfaces. 2019 Feb 27;11(8):8242-8249. doi: 10.1021/acsami.8b20400. Epub 2019 Feb 14.
Poor stability always restricts the application of all-inorganic perovskite quantum dots (PQDs). Herein, 2D hexagonal boron nitride ( h-BN) nanosheets were firstly utilized to stabilize CsPbBr PQDs through a facile heterogeneous nucleation-growth process at room temperature. In synthesized h-BN/CsPbBr PQD nanocomposites, cubic CsPbBr PQDs adhere on h-BN nanosheet surfaces, benefiting from the high specific surface area and abundant mesopores of 2D nanosheets. The nanocomposites prepared at optimized loading of h-BN nanosheets and reaction time display good green-emitting performance with a narrow full width at half maximum of ∼20.0 nm and high color purity of 92.0%. Unique 2D structure and excellent thermal conductivity of h-BN nanosheets endow the h-BN/CsPbBr PQD nanocomposites with significantly enhanced humidity stability and thermal stability. The white light-emitting diodes (LEDs) assembled with green-emitting nanocomposites, a blue chip, and a commercial red phosphor possess a low correlated color temperature of 4190 K, color-rendering index of 76, and high luminous efficacy of 57 lm/W. Further, the color gamut of the synthetic white light based on blue-emitting h-BN/CsPbBrCl PQDs, green-emitting h-BN/CsPbBr PQDs, and red-emitting h-BN/CsPbBrI PQDs is 114% of the National Television System Committee standard. This work paves a new way for utilizing 2D nanomaterials to synthesize stable all-inorganic PQDs for white LEDs and displays.
较差的稳定性一直限制着全无机钙钛矿量子点（PQDs）的应用。在此，通过在室温下的简便异质成核-生长过程，首次利用二维六方氮化硼（h-BN）纳米片来稳定 CsPbBr PQDs。在合成的 h-BN/CsPbBr PQD 纳米复合材料中，立方 CsPbBr PQDs 附着在 h-BN 纳米片表面上，这得益于二维纳米片的高比表面积和丰富的中孔。在优化 h-BN 纳米片负载量和反应时间下制备的纳米复合材料显示出良好的绿光发射性能，半峰全宽约为 20.0nm，颜色纯度高达 92.0%。h-BN 纳米片独特的二维结构和优异的导热性能赋予 h-BN/CsPbBr PQD 纳米复合材料显著增强的湿度稳定性和热稳定性。组装有绿光发射纳米复合材料、蓝色芯片和商用红色荧光粉的白色发光二极管（LEDs）具有低相关色温 4190K、显色指数 76 和高光效 57lm/W。此外，基于蓝色发射 h-BN/CsPbBrCl PQDs、绿色发射 h-BN/CsPbBr PQDs 和红色发射 h-BN/CsPbBrI PQDs 的合成白光的色域是国家电视系统委员会标准的 114%。这项工作为利用二维纳米材料合成用于白色 LED 和显示器的稳定全无机 PQDs 开辟了一条新途径。
