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A Red-Emitting Cu(I)-Halide Cluster Phosphor with Near-Unity Photoluminescence Efficiency for High-Power wLED Applications.

ABSTRACT: Solid-state lighting technology, where light-emitting diodes (LEDs) are used for energy conversion from electricity to light, is considered a next-generation lighting technology. One of the significant challenges in the field is the synthesis of high-efficiency phosphors for designing phosphor-converted white LEDs under high flux operating currents. Here, we reported the synthesis, structure, and photophysical properties of a tetranuclear Cu(I)-halide cluster phosphor, [bppmCu₂I₂]₂ (bppm = bisdiphenylphosphinemethane), for the fabrication of high-performance white LEDs. The PL investigations demonstrated that the red emission exhibits a near-unity photoluminescence quantum yield at room temperature and unusual spectral broadening with increasing temperature in the crystalline state. Considering the excellent photophysical properties, the crystalline sample of [bppmCu₂I₂]₂ was successfully applied for the fabrication of phosphor-converted white LEDs. The prototype white LED device exhibited a continuous rise in brightness in the range of a high bias current (100-1000 mA) with CRI as high as 84 and CCT of 5828 K, implying great potential for high-quality white LEDs.

SUBMITTER: Zhaxi W

PROVIDER: S-EPMC9318059 | biostudies-literature |

REPOSITORIES: biostudies-literature

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