Site Substitution Triggered Luminescence Characteristics Modulation in Eu3+‐Activated Sr4La6(SiO4)6Cl2 Phosphors for Boosting Viral Resistance and Plant Growth

Abstract A series of Eu 3+ ‐activated Sr 4 La 6 (SiO 4 ) 6 Cl 2 (SLSCl) phosphors are prepared to fulfill the requirements of plant growth and immunity. Upon 394 nm excitation, the resulting phosphors can emit intense red emission from Eu 3+ , of which their intensities are sensitive to dopant content and site occupation. When Eu 3+ occupies La 3+ and Sr 2+ sites, its optimal doping contents in SLSCl host lattices is 40 and 50 mol%, respectively. Moreover, the quantum efficiency and thermal stability of designed phosphors are also greatly dependent on the site taken by Eu 3+ in SLSCl host lattices. Via utilizing the designed phosphors as red‐emitting converters, two different light‐emitting diodes (LEDs) are fabricated, whose emission bands overlap with the absorption bands of plant pigments, enabling their feasibilities in plant growth. Furthermore, the plant growth experiments indicate that the photosynthesis can be significantly improved via employing the packaged LEDs as supplementary lights. Additionally, the packaged red‐emitting LEDs can enhance the resistance of the N. benthamiana plants against viral infection. The findings do not only propose a facile route to manipulate the luminescence properties of Eu 3+ ‐activated phosphors, but also confirm that the utilization of red light as supplementary light is an efficient to promote plant growth and viral resistance.