Synthesis and optimization of Dy-doped SrZr4(PO4)6 nanophosphors for plant growth light-emitting diodes

Abstract Indoor plant growth can protect crops from damage caused by climate variations in outdoor lighting systems. For indoor plant cultivation, artificial light sources are needed to enhance the plant growth. Regarding this problem, a series of SrZr4(PO4)6:Dy3+ nanophosphors with various concentrations of dopant ions were synthesized using a sol-gel method. The Rietveld refinement method confirmed that existence of the impurity phases in the synthesized phosphors. The elemental state and chemical composition of the host and dopant (Dy3+) were analyzed by X-ray photoelectron spectroscopy (XPS). The surface morphology was examined by field emission scanning electron microscopy (FESEM), and the nanostructure was confirmed by high-resolution transmission electron microscopy (HRTEM). The photoluminescence (PL) spectra consisted of broad peaks in the range of 460–510 nm (blue), 560–596 nm (yellow), 602–651 nm (red), and 743–773 nm (near-infrared), which were exited at a wavelength of 349 nm. The emission spectra were suitable for the absorption band of phytochromes of plants, showing that the SrZr4(PO4)6:Dy3+ nanophosphor may have potential applications in plant growth promoted by light-emitting diodes (LEDs).