Color-pure red light-emitting diodes based on two-dimensional lead-free perovskites.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33055155.
- Also identified by DOI 10.1126/sciadv.abb0253 and PMC identifier 7556835.
- Licence recorded as CC BY-NC.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
It remains a central challenge to the information display community to develop red light-emitting diodes (LEDs) that meet demanding color coordinate requirements for wide color gamut displays. Here, we report high-efficiency, lead-free (PEA)<sub>2</sub>SnI<sub>4</sub> perovskite LEDs (PeLEDs) with color coordinates (0.708, 0.292) that fulfill the Rec. 2100 specification for red emitters. Using valeric acid (VA)-which we show to be strongly coordinated to Sn<sup>2+</sup>-we slow the crystallization rate of the perovskite, improving the film morphology. The incorporation of VA also protects tin from undesired oxidation during the film-forming process. The improved films and the reduced Sn<sup>4+</sup> content enable PeLEDs with an external quantum efficiency of 5% and an operating half-life exceeding 15 hours at an initial brightness of 20 cd/m<sup>2</sup> This work illustrates the potential of Cd- and Pb-free PeLEDs for display technology.