Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
College of Chemistry, National & Local United Engineering Laboratory for Power Batteries, Northeast Normal University, 5268, Renmin Street, Changchun, 130024, P. R. China.
Adv Mater. 2017 Sep;29(34). doi: 10.1002/adma.201701153. Epub 2017 Jul 10.
Whereas organic-inorganic hybrid perovskite nanocrystals (PNCs) have remarkable potential in the development of optoelectronic materials, their relatively poor chemical and colloidal stability undermines their performance in optoelectronic devices. Herein, this issue is addressed by passivating PNCs with a class of chemically addressable ligands. The robust ligands effectively protect the PNC surfaces, enhance PNC solution processability, and can be chemically addressed by thermally induced crosslinking or radical-induced polymerization. This thin polymer shield further enhances the photoluminescence quantum yields by removing surface trap states. Crosslinked methylammonium lead bromide (MAPbBr ) PNCs are applied as active materials to build light-emitting diodes that have low turn-on voltages and achieve a record luminance of over 7000 cd m , around threefold better than previous reported MA-based PNC devices. These results indicate the great potential of this ligand passivation approach for long lifespan, highly efficient PNC light emitters.
虽然有机-无机杂化钙钛矿纳米晶体（PNCs）在光电材料的发展中具有显著的潜力，但它们相对较差的化学和胶体稳定性削弱了它们在光电设备中的性能。在此，通过用一类可化学寻址的配体对 PNC 进行钝化来解决这个问题。坚固的配体可以有效地保护 PNC 表面，提高 PNC 溶液加工性能，并可通过热诱导交联或自由基诱导聚合进行化学寻址。这种薄的聚合物屏蔽层通过去除表面陷阱状态进一步提高了光致发光量子产率。交联的甲脒铅溴（MAPbBr ）PNC 被用作活性材料来构建发光二极管，其开启电压较低，并实现了超过 7000 cd/m 的创纪录亮度，比以前报道的基于 MA 的 PNC 器件好三倍。这些结果表明，这种配体钝化方法在长寿命、高效 PNC 发光体方面具有巨大的潜力。
