Rare-Earth-Element Free Yellow Phosphors for White Light-Emitting Diodes

Yellow phosphor emits white light when excited with the 460 nm blue lighting. The blue LED (left half; top) when coated with dispersed yellow phosphor (right half; top) emits white light.


Invention Summary:

Despite their low energy consumption and higher efficiency, white light-emitting diodes made of blue chip coupled with yellow phosphor has disadvantages of high correlated color temperature, relatively low color rendering index and the use of rare-earth elements (REE).

Rutgers researchers have developed a new REE-free yellow phosphor made of metal organic frameworks (MOFs) which emit yellow light upon excitation with blue light. It is achieved through a metal/ligand combination, where a highly emissive molecular fluorophore is combined with a bandgap regulating co-ligand into a MOF structure. This tunes the HOMO-LUMO energy gap to attain desired excitation and emission properties. The fabrication process of this invention can be repurposed to many other metal/ligand combinations.

Market Applications:

  • Commercial/ industrial lighting
  • Horticulture lighting
  • Sports flood lighting

Advantages:

  • 100% free of REEs
  • Highest internal quantum yield of 90.7% among all the reported, blue-excited yellow phosphors
  • High solution processability
 

Intellectual Property & Development Status: Patents issued in the USA (US 10800968 B2), Canada (CN 106459095B), EP (EP 3134416B1), and JP (JP 6731855 B2). Available for licensing and/or research collaboration. For any business development and other collaborative partnerships contact marketingbd@research.rutgers.edu

 

Patent Information: