Synergistic enhancement effect of Nb5+ Co-doping on the luminescent properties of SrTiO3:Eu3+ phosphors

Red fluorescent powder has important applications in various fields such as display and lighting. In this paper, Eu 3+ /Nb 5+ co-doped SrTiO 3 fluorescent material was synthesized by hydrothermal method, and its phase structure, microstructure, luminescence properties, thermal stability and luminescence dynamic characteristics were systematically characterized. The results showed that under 395 nm near-ultraviolet excitation, the material emitted high-purity Eu 3+ characteristic red light at 612 nm; when the Eu 3+ doping content was 7 mol% and Nb 5+ was 3.5 mol%, the luminescence intensity was increased by 259% compared with single-doped Eu 3+ ,and the absolute quantum efficiency increased. Nb 5+ plays a dual role in this process, namely charge compensation and energy transfer modulation: On one hand, it inhibits the formation of lattice defects through charge balance between sites; on the other hand, it constructs an efficient light absorption center, enabling ultrafast energy transfer from the matrix to Eu 3+ . This material has stable color properties within the temperature range of 303-463 K, with no obvious color shift, and the thermal quenching activation energy is 0.34 eV, showing excellent thermal stability. This efficient and stable red fluorescent powder prepared by the Eu 3+ /Nb 5+ co-doping strategy has broad application prospects in near-ultraviolet excitation high color rendering index white LED and anti-counterfeiting encryption fields.