ABSTRACT

This work investigated the photoluminescence behaviour of Tb³⁺ doped BiPO₄ nanophosphors synthesised by co-precipitation method using ethylene glycol. The prepared nanophosphors were characterised by XRD, SEM, FT-IR and PL spectroscopy techniques. Monoclinic phase was observed from the XRD and FT-IR studies. SEM image showed agglomeration of nanoparticles. In the emission spectra, band originated from ³P₁–¹S₀ transition of Bi³⁺ ion and bands due to ⁵D₄ → ⁷F_6,5,4,3 transitions of doping Tb³⁺ ion were observed upon excitation at 351 nm. The emission intensity was found to accentuate with the increase in Tb³⁺ ion concentration upto 3at. % and subsequently attenuated with further increase in Tb³⁺ ion concentration due to concentration quenching effect. The decay time of the prepared phosphors was also investigated. The CIE chromaticity diagram revealed a nearly white colour emission upon excited at 351 nm. It is possible that the prepared phosphors may be useful for solid-state lighting.

摘要

本工作研究了乙二醇共沉淀法合成的Tb ³⁺掺杂BiPO _{4纳米荧光粉的光致发光行为。}通过XRD、SEM、FT-IR和PL光谱技术对制备的纳米荧光粉进行了表征。从 XRD 和 FT-IR 研究中观察到单斜晶相。SEM图像显示纳米颗粒的团聚。在发射光谱中，谱带源于Bi ³⁺离子的³ P ₁ – ¹ S ₀跃迁，谱带源于掺杂Tb ^3+的5 D ₄ → ⁷ F _{6,5,4,3跃迁}在 351 nm 激发时观察到离子。发现发射强度随着Tb ³⁺离子浓度增加到3at而增强。% 并且随后由于浓度猝灭效应而随着 Tb ³⁺离子浓度的进一步增加而减弱。还研究了制备的磷光体的衰减时间。CIE 色度图显示在 351 nm 处激发时发射近乎白色的颜色。制备的磷光体可能对固态照明有用。