High thermal stability near-infrared aluminoborate phosphor with spectral tunability and its rice lighting application

Cr 3+ -activated near-infrared (NIR) phosphors have great potential in plant lighting, noninvasive detection, iris recognition, etc. Herein, an aluminoborate host material with a wide band gap (E g  = 4.60 eV) and high Debye temperature is selected to prepare a NIR phosphor Al 5 BO 9 : Cr 3+ (ABO: Cr 3+ ). The phosphor exhibits typical intermediate crystal field luminescence and has a high degree of matching with plant phytochrome. The photoluminescence intensity at 150 °C retains 91.1 % at room temperature. In addition, the spectral redshift (730 nm–770 nm) is achieved through the crystal field modulation, which is beneficial to broaden its application scenarios, such as plant antiviral immunity, night vision and noninvasive detection. Finally, the rice cultivation experiment confirms that the supplement of NIR light promotes growth, stress resistance and leaf angle of rice seedlings.