Colloidal quantum dots (CQDs) are emerging as promising materials for constructing infrared sources in view of their tunable luminescence, high quantum efficiency and compatibility with solution processing However, CQD films available today suffer from a compromise between luminescence efficiency and charge transport, and this leads to unacceptably high power consumption. Here, we overcome this issue by embedding CQDs in a high-mobility hybrid perovskite matrix. The new composite enhances radiative recombination in the dots by preventing transport-assisted trapping losses; yet does so without increasing the turn-on voltage. Through compositional engineering of the mixed halide matrix, we achieve a record electroluminescence power conversion efficiency of 4.9%. This surpasses the performance of previously reported CQD near-infrared devices two-fold, indicating great potential for this hybrid QD-in-perovskite approach.

Nature Photonics 10, 253–257 (2016) doi:10.1038/nphoton.2016.11
Received 17 April 2015 Accepted 15 January 2016 Published online 22 February 2016

http://www.nature.com/nphoton/journal/v10/n4/full/nphoton.2016.11.html

胶体量子点（CQDs）由于具有光谱可调节、量子效率高、可溶液加工等优点，是制备近红外光源的理想材料。不过，当前工艺得到的CQD薄膜仍存在一些问题，例如发光效率与电荷传输无法同时达到最优状态，这带来了严重的能耗问题。Gong等人利用将CQDs嵌入到高迁移率的杂化钙钛矿基底中的办法，解决了这一问题。他们制备的新型复合材料提高了辐射复合的效率，同时不会牺牲启亮电压。以这种材料制备的器件，电致发光效率可以达到4.9%，是目前同类器件中的最高效率。（Nature Photonics DOI: 10.1038/NPHOTON.2016.11）（新材料在线）