NaYF(4):Er(3+),Yb(3+)/SiO(2) Core/Shell Upconverting Nanocrystals for Luminescence Thermometry up to 900 K.
NaYF(4):Er(3+),Yb(3+)/SiO(2) Core/Shell Upconverting Nanocrystals for Luminescence Thermometry up to 900 K.
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DOI：
10.1021/acs.jpcc.6b10279
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发表时间：
2017-02-16
期刊：
影响因子：
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通讯作者：
Meijerink A
中科院分区：
文献类型：
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作者：
Geitenbeek RG;Prins PT;Albrecht W;van Blaaderen A;Weckhuysen BM;Meijerink A
具有独特尺寸可调特性的纳米材料的快速发展为包括温度传感在内的多种新应用奠定了基础。发光纳米粒子（NPs）已显示出作为灵敏纳米温度计的潜力，特别是在生物系统中。它们的小尺寸为绘制具有高空间分辨率的温度分布提供了可能。然而，其温度范围有限，这阻碍了它们在高温应用中的使用，例如纳米电子学、热障涂层和化学反应器等。在这项工作中，我们使用掺杂镧系离子Yb³⁺和Er³⁺的二氧化硅包覆的NaYF₄纳米粒子，将纳米测温的温度范围扩展到900 K以上。单分散的约20 nm的NaYF₄:Yb,Er纳米晶体被一层约10 nm的二氧化硅壳层包覆。在用红外辐射激发时，观察到明亮的绿色上转换（UC）发射。根据分别位于520 nm和550 nm的²H₁₁/₂和⁴S₃/₂上转换发射谱线之间的强度比，对于二氧化硅包覆的纳米粒子，温度可测定到至少900 K，精度为1 - 5 K。对于未包覆的NaYF₄:Yb,Er纳米粒子，粒子在600 K以上会降解。重复的热循环实验表明，二氧化硅包覆的纳米晶体作为温度探针具有高耐久性和可重复性，且性能没有任何损失。目前的研究结果为通过在多种镧系掺杂的纳米粒子周围施加二氧化硅涂层来开发一类新型的高度稳定的纳米探针开辟了途径。
The rapid development of nanomaterials with unique size-tunable properties forms the basis for a variety of new applications, including temperature sensing. Luminescent nanoparticles (NPs) have demonstrated potential as sensitive nanothermometers, especially in biological systems. Their small size offers the possibility of mapping temperature profiles with high spatial resolution. The temperature range is however limited, which prevents use in high-temperature applications such as, for example, nanoelectronics, thermal barrier coatings, and chemical reactors. In this work, we extend the temperature range for nanothermometry beyond 900 K using silica-coated NaYF4 nanoparticles doped with the lanthanide ions Yb3+ and Er3+. Monodisperse ∼20 nm NaYF4:Yb,Er nanocrystals were coated with a ∼10 nm silica shell. Upon excitation with infrared radiation, bright green upconversion (UC) emission is observed. From the intensity ratio between 2H11/2 and 4S3/2 UC emission lines at 520 and 550 nm, respectively, the temperature can be determined up to at least 900 K with an accuracy of 1–5 K for silica-coated NPs. For bare NaYF4:Yb,Er NPs, the particles degrade above 600 K. Repeated thermal cycling experiments demonstrate the high durability and reproducibility of the silica-coated nanocrystals as temperature probes without any loss of performance. The present results open avenues for the development of a new class of highly stable nanoprobes by applying a silica coating around a wide variety of lanthanide-doped NPs.