Laboratoire de Physique Appliquée, Groupe des Matériaux Luminescents, Faculté des Sciences de Sfax, Département de Physique, Université de Sfax, BP, 1171, Sfax, Tunisia.
Departamento de Fisica, Universidad de La Laguna, Apartado 456, 38200 San Cristobal de La Laguna, Santa Cruz de Tenerife, Spain.
Dalton Trans. 2022 Mar 29;51(13):5108-5117. doi: 10.1039/d1dt03747a.
In the last few years, huge progress has been made in the development of remote optical thermometry strategies, due to their non-contact, high-sensitivity and fast measurement characteristics, which are especially important for various industrial and bio-applications. For these purposes, lanthanide-doped particles seem to be the most promising luminescence thermometers. In this study, Tm/Yb:NaGdVO (NGVO) phosphors were prepared using a sol-gel method. Under 980 nm excitation, the upconversion (UC) and down-shifting (DS) emission spectra are composed of two visible emission bands arising from the Tm transitions G → H (475 nm) and G → F (651 nm), a strong emission at 800 nm (H → H) in the first biological window and emission in the third biological window at 1625 nm (F → H), respectively. Accordingly, the luminescence intensity ratio (LIR) between the Tm LIR (800/475) and LIR (1625/475) transitions demonstrates excellent relative sensing sensitivity values (4.2% K-2% K) and low-temperature uncertainties (0.4 K-0.5 K) over a wide temperature sensing range of 300 K to 565 K, which are remarkably better than those of many other luminescence thermometers. This phosphor exhibits strong NIR emission at low excitation density, meaning that it has potential uses in deep tissue imaging, optical signal amplification and other fields. The results indicate that Tm/Yb:NGVO is an ideal candidate for thermometers and particularly for biological applications.
在过去的几年中，由于远程光学测温策略具有非接触、高灵敏度和快速测量的特点，在各种工业和生物应用中尤为重要，因此在远程光学测温策略的发展方面取得了巨大进展。对于这些目的，镧系掺杂粒子似乎是最有前途的发光温度计。在这项研究中，使用溶胶-凝胶法制备了 Tm/Yb:NaGdVO（NGVO）荧光粉。在 980nm 激发下，上转换（UC）和下转换（DS）发射光谱由两个可见光发射带组成，这两个发射带分别源于 Tm 跃迁 G→H（475nm）和 G→F（651nm）、在第一生物窗口中强发射 800nm（H→H）以及在第三生物窗口中发射 1625nm（F→H）。相应地，Tm LIR（800/475）和 LIR（1625/475）跃迁之间的发光强度比（LIR）表现出优异的相对传感灵敏度值（4.2% K-2% K）和低温不确定度（0.4 K-0.5 K），在 300 K 至 565 K 的宽温度传感范围内，这明显优于许多其他发光温度计。该荧光粉在低激发密度下表现出强近红外发射，这意味着它在深部组织成像、光学信号放大等领域具有潜在的应用。结果表明，Tm/Yb:NGVO 是一种理想的温度计候选材料，特别适用于生物应用。
