Although the solid-state lighting industry has achieved huge successes in both red and blue part of the visible spectrum during the last 40 years, light-emitting diodes (LEDs) that emit green light consistently exhibit inferior efficiencies. Thanks to the use of down-conversion phosphors, white LEDs have been commercialised without using green LEDs. However, the efficiency problem of green LEDs still hinders many potential applications of solid-state lighting and limits the overall system efficiency. This review first attempts to conclude and comment on the complex factors that limit the performance of green LEDs with recent research progresses. Then the article focuses on reviewing various strategies to improve green light LED radiative recombination efficiencies.
This review was chosen as a runner up of the 2018 Materials Literature Review Prize of the Institute of Materials, Minerals and Mining, run by the Editorial Board of MST. Sponsorship of the prize by TWI Ltd is gratefully acknowledged.
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