High temperature solid-phase synthesis of Al/Y-doped Na4CaSi3O9:Bi3+,Eu3+ phosphors with tunable emission spectra for light-conversion applications

Both Al 3+ and Y 3+ ions co-doped Na 4 CaSi 3 O 9 :Bi 3+ ,Eu 3+ (NCSO:Bi 3+ ,Eu 3+ ) series phosphors were synthesized by a high temperature solid-phase method, and characterized by various advanced structural and spectral instruments. The impact of different doping ion concentrations on the luminescent behavior of the phosphors was also investigated. It is found that an ion substitution strategy is useful for enhancing the luminescence performance of the as-obtained NCSO:Bi 3+ ,Eu 3+ phosphors. The results show that doping a certain amount of Al 3+ ions into the NCSO:0.01Bi 3+ ,0.1Eu 3+ phosphor leads to a significant red-shift in the blue emission spectrum of Bi 3+ up from 350 to 405 nm and an increase in the half-peak width by 21 nm, better spectral match for plant response. Furthermore, doping Y 3+ ions into the matrix also enhances the sensitization effect of Bi 3+ ions, resulting in a significant increase in luminous intensity. X-ray powder diffraction (XRD) was used to verify the crystal structure and phase purity of the synthesized phosphors. The mechanism of Al 3+ and Y 3+ doping affecting the emission spectrum is further discussed through the structure refinement. Finally, by comparing with the absorption spectra of plant growth pigments, it is found that the developed phosphors show great potential in promoting light controlling for plant growth.