Highly Stable Ca3Bi(PO4)3: Eu3+ Red Phosphors Dual-Functional Applications from Plant Growth Lighting to High-Ra White LEDs

To advance artificial-light plant cultivation and high-performance white light-emitting diodes (LEDs), a phosphor combining excellent luminous thermal stability with superior luminescence is essential. In this work, the high-thermal-stability Ca 3 Bi(PO 4 ) 3 (CBPO): Eu 3+ red phosphors were successfully synthesized via high-temperature solid-state method. The performance of LEDs fabricated with the phosphors is enhanced in the far-red light region. When combined with commercial blue and green phosphors, the resulting white LEDs achieve high color rendering index (R a = 90.3) and low correlated color temperature (CCT = 4898 K). Upon near-ultraviolet (n-UV) excitation, the CBPO: Eu 3+ phosphors exhibit bright red emission at 615 nm, achieving optimal performance at a doping concentration of 0.24. At temperature of 423 K (150 °C), the luminescence intensity of the CBPO: 0.24Eu 3+ phosphor retained 71.9% of room-temperature value, demonstrating its good luminous thermal stability. The fabricated red LEDs with high color purity and spectral characteristics closely matching the absorption properties of plant photosensitive receptor proteins, enhance photosynthetic efficiency and underscore their substantial application potential in plant growth. The fabricated white LEDs can emit bright white light, with R a and R 9 values of 90.3 and 62, which are significantly higher than the standard R a (80) and R 9 (30) of commercial phosphors. We conducted a plant growth experiment in the laboratory, demonstrating that the fabricated red LEDs effectively supplement plant illumination and promote growth. These results demonstrate that the prepared CBPO: Eu 3+ red phosphors hold significant potential for applications in both plant growth lighting and white LEDs.