Blue-red dual color emitting phosphor Cs2NaLuCl6: Sb3+, Ho3+ for plant growth LEDs

Abstract

The phosphor-converted light emitting diode (pc-LED) is an efficient light source to adjust growth rhythm and raise yield of plant. Blue and red light play the dominant role in the process of plant growth, thus it is meaningful to search the blue-red dual emission phosphors with high quantum field and better thermal stability for developing plant growth LED. Herein, the blue-red dual emission phosphors were synthesized by co-doping Sb3+ and Ho3+ into the Cs2NaLuCl6, which emitted blue (454 nm) to red (657 nm) light with increasing the content of Ho3+ to 25% and their relative intensity could be tuned through adjusting the concentration of Ho3+ due to the efficient energy transfer from Sb3+ to Ho3+. The intensity of blue emission from Sb3+ and red emission from Ho3+ could maintain 78.4 and 75.8% of the room temperature at 150 °C, respectively. Furthermore, the spectra of fabricated blue and red LEDs match well with the absorption of carotenoid, Phytochrome and Chlorophyll b, implying the samples possess great application potential in plant growth LED.