A series of YNbO₄:Bi³⁺ and YNbO₄:Bi³⁺/Er³⁺ phosphors were prepared by a conventional high temperature solid–state reaction method. The results of XRD and Rietveld refinement confirm that monoclinic phase YNbO₄ samples are achieved. The down-/up-conversion luminescence of Er³⁺ ions was investigated under the excitation of ultraviolet light (327 nm) and near infrared light (980 nm). Under 327 nm excitation, broad visible emission band from Bi³⁺ ions and characteristic green emission peaks from Er³⁺ ions are simultaneously observed, while only strong green emissions from Er³⁺ ions are detected upon excitation of 980 nm. Remarkable emission enhancement is observed in down-/up-conversion luminescence processes by introducing Bi³⁺ ions into Er³⁺-doped YNbO₄ phosphors. Pumped current versus up-conversion emission intensity study shows that two-photon processes are responsible for both the green and the red up-conversion emissions of Er³⁺ ion. Through the study of the temperature sensing property of Er³⁺ ion, it is affirmed that the temperature sensitivity is sensitive to the doping concentration of Bi³⁺ ions. By comparing the experimental values of the radiative transition rate ratio of the two green emission levels of Er³⁺ ions and the theoretical values calculated by Judd-Ofelt (J-O) theory, it is concluded that the temperature sensing property of Er³⁺ ions is greatly affected by the energy level splitting.

通过常规高温固相反应法制备了一系列YNbO ₄ :Bi ³⁺和YNbO ₄ :Bi ³⁺ /Er ^{3+荧光粉。}XRD 和Rietveld 精修结果证实获得了单斜晶相YNbO ₄样品。在紫外光（327 nm）和近红外光（980 nm）的激发下研究了Er ^{3+离子的下/上转换发光。}在 327 nm 激发下，同时观察到来自 Bi ³⁺离子的宽可见发射带和来自 Er ³⁺离子的特征绿色发射峰，而来自 Er ^{3+的只有强绿色发射}在 980 nm 的激发下检测离子。^{通过将Bi 3+}离子引入Er ³⁺掺杂的YNbO ₄荧光粉，在下/上转换发光过程中观察到显着的发射增强。泵浦电流与上转换发射强度的研究表明，双光子过程负责 Er ³⁺离子的绿色和红色上转换发射。通过对Er ³⁺离子的温度传感特性的研究，肯定了温度敏感性对Bi ³⁺离子的掺杂浓度敏感。^{通过比较 Er 3+}两个绿色发射能级的辐射跃迁率比的实验值离子和Judd-Ofelt（JO）理论计算的理论值，得出Er ³⁺离子的温度传感特性受能级分裂的影响很大。