Enhanced color rendering index of organic/inorganic hybrid white light-emitting diodes with trans-1-(9-anthryl)-2-phenylethene derivatives as organic blue-green emitting materials

Abstract The organic light-emitting materials have made certain development in organic/inorganic hybrid white light-emitting diodes (WLED) devices, which can reduce the reliance on rare earth metal materials to some extent. However, there is an urgent need to improve the color rendering index (CRI) of the hybrid WLED. Herein, the organic blue-green emitting materials mixed with green and red phosphors are used to construct the hybrid WLED. The device W19 is prepared by using the blue-green emitting material (E)-9-(4-(2-(anthracen-9-yl)vinyl)phenyl)-10-(naphthalen-1-yl)anthracene (APEAn1N) mixed with green (BaSi2N2O2: Eu2+) and red (Sr, Ca)2AlSiN3: Eu2+ phosphors coated on near ultraviolet (NUV) LED chips (380 nm). The device W19 exhibits luminance efficiency of 17.78 lm W−1 (at 19.90 mA), CCT of 4658 K, CRI of 86.7, and CIE chromaticity coordinate of (0.3633, 0.4125), respectively. The CRI of device W22 based on tri-primary color phosphors and blue-green phosphor is 79.4 which is inferior to W19. The WLED device based on organic blue-green emitting materials blended with green and red phosphors has evident advantages for reducing of the reliance on rare earth metals and improving the CRI of hybrid device, which will greatly inspire us to design and synthesize new blue-green materials and facilitate the development of hybrid WLEDs in future.