Site occupancy of Sm3+, Pr3+, Tb3+ in Na5Y(WO4)4 and their photoluminescence spectra for application in plant growth LED and fingerprint detection

This study successfully synthesized Na 5 Y(WO 4 ) 4 doped with Sm³⁺, Pr³⁺, and Tb³⁺ using a high-temperature solid-state method. Photoluminescence spectra revealed that Na 5 Y(WO 4 ) 4 :Sm³⁺ phosphors emits a strong red glow at 646 nm under the excitation of 405 nm, and has an extremely high quantum yield, suggesting their suitability for plant growth LED lighting applications. In contrast, Na 5 Y(WO 4 ) 4 :Pr³⁺ phosphors displayed a lower efficiency but still aligned well with the red-wavelength absorption spectra of plants. Additionally, Na 5 Y(WO 4 ) 4 :Tb³⁺ phosphors demonstrated strong green emission under UV light, indicating potential applications in fingerprint detection. The Site Occupancy Theory (SOT) was utilized to explain the preferential occupation of dopant ions, showing that Sm³⁺ and Tb³⁺ preferred Y1 sites, whereas Pr³⁺ favored Na2 sites.