高灵敏度下转换光学测温材料:NaGd(WO4)2:Yb3+/Er3+ -

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高灵敏度下转换光学测温材料:NaGd(WO₄)₂:Yb³⁺/Er³⁺

doi:10.3788/CO.20191203.0596

河北大学物理科学与技术学院河北省光电信息材料重点实验室新能源光电器件国家地方联合工程实验室, 河北保定 071002

基金项目:

国家自然科学基金11474083

河北省自然科学基金A2015201192

河北省教育厅科研项目ZD2014069

详细信息

作者简介:
李晓晓(1995—)，女，河北邯郸人，硕士研究生，2016年于河北师范大学获得学士学位，主要从事无机发光材料方面的研究。E-mai:leexiaoxiaolxx@163.com
杨艳民(1972—)，男，内蒙古赤峰人，博士，教授，2008年于中国科学院长春光学精密机械与物理研究所获得博士学位，主要从事无机发光材料方面的研究。E-mail:mihuyym@163.com

中图分类号:O482.31
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出版历程
- 收稿日期:2018-11-08
- 修回日期:2018-12-07
- 刊出日期:2019-06-01

Highly sensitive down-conversion optical temperature-measurement material: NaGd(WO₄)₂: Yb³⁺/Er³⁺

College of Physics Science and Technology, Hebei University, Hebei Key Lab of Optic-electronic Information and Materials, National and Regional Joint EngineeringLab of New Energy Optic-electronic Devices, Baoding 071002, China

Funds:

National Natural Science Foundation of China11474083

Natural Science Foundation of Hebei ProvinceA2015201192

Scientific Research Project of Hebei Education DepartmentZD2014069

More Information

Corresponding author:YANG Yan-min, E-mail:mihuyym@163.com

摘要

摘要:基于Er ³⁺的两个热耦合能级发光强度测量的荧光强度比测温技术由于不受光谱损失和激发强度波动的影响，故能够提供准确的非接触式温度测量。但目前通用的荧光强度比技术都是基于上转换激发，而上转换材料效率较低，测温不准确。考虑到Er ³⁺能级可通过不同激发源来布居，本文利用高能光子激发的高效下转换光学测温方法，来解决上转换发光带来的问题，并以具有高测温灵敏度的钨酸盐NaGd（WO ₄） ₂为基质。研究发现，NaGd（WO ₄） ₂可成功用于下转换测温，Yb ³⁺/Er ³⁺共掺样品比Er ³⁺单掺拥有更高的测温灵敏度，且下转换测温灵敏度要高于上转换，在掺杂浓度为20% Yb ³⁺/1% Er ³⁺时，测温灵敏度高达344.6×10 ^-4K ^-1。这证明了NaGd（WO ₄） ₂：Yb ³⁺/Er ³⁺是理想的测温材料，也很好地验证了其在高灵敏度下转换测温的可行性，为荧光强度比技术的应用开辟了新的前景。
- 荧光强度比测温/
- 光学测温/
- 高灵敏度/
- 钨酸盐/
- 上转换/
- 下转换
Abstract:The fluorescence intensity ratio(FIR) thermometry based on the measurement of luminous intensities of two thermal coupling energy levels of Er ³⁺provides high precision for the non-contacted thermometry due to its independency of the spectral loss and excitation intensity fluctuations. However, the common FIR technology is based on the up-conversion(UC) excitation, and its low up-conversion efficiency makes the temperature measurement inaccurate. Considering that the thermalization of population in Er ³⁺can be achieved by different excitation sources, we utilize the efficient down-conversion(DC) optical temperature measurement with a high-energy photon excitation. A tungstate material of NaGd(WO ₄) ₂with high temperature sensitivity is used as the matrix material. It is found that NaGd(WO ₄) ₂can be successfully applied for the DC thermometry, and the temperature sensitivity of Yb ³⁺/Er ³⁺co-doped sample is higher than that of Er ³⁺single-doped one. In addition, the DC thermometry possesses higher sensitivity than UC, and the temperature sensitivity of 20%Yb ³⁺/1%Er ³⁺doped sample is up to 344.6×10 ^-4K ^-1, which demonstrates that NaGd(WO ₄) ₂:Yb ³⁺/Er ³⁺is an ideal temperature measuring material. More importantly, it further proves the feasibility of highly sensitive DC thermometry and opens up new prospects for the utilizations of FIR technology.
- fluorescence intensity ratio(FIR) thermometry/
- optical thermometry/
- high sensitivity/
- tungstate/
- up-conversion/
- down-conversion

HTML全文

图 1NaGd(WO₄)₂:1%Er³⁺及NaGd(WO₄)₂:1%Yb³⁺/1%Er³⁺样品的XRD图谱

Figure 1.XRD spectrum patterns of NaGd(WO₄)₂:1%Er³⁺and NaGd(WO₄)₂:1%Yb³⁺/1%Er³⁺samples

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图 2(a) NaGd(WO₄)₂:1%Er³⁺的SEM图；(b)NaGd(WO₄)₂:1%Yb³⁺/1%Er³⁺的SEM图

Figure 2.(a)SEM image of NaGd(WO₄)₂:1%Er³⁺; (b)SEM image of NaGd(WO₄)₂:1%Yb³⁺/1%Er³⁺

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图 3(a) 1%Er³⁺单掺杂样品处于不同温度(303 K, 433 K and 563 K)时的980 nm激发上转换发射谱；(b)1%Yb³⁺/1%Er³⁺共掺杂样品处于不同温度(303 K, 433 K and 563 K)时的980 nm激发上转换发射谱。图中均对552 nm处的峰进行了归一化

Figure 3.(a)UC spectra of 1%Er³⁺-doped sample at different temperatures(303 K, 433 K and 563 K) excited with 980 nm; (b)UC spectra of 1%Yb³⁺/1%Er³⁺co-doped sample at different temperatures(303 K, 433 K and 563 K) excited with 980 nm. The spectra were normalized at 552 nm

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图 4(a) 1%Er³⁺单掺杂样品在980 nm上转换激发下的荧光强度比R与绝对温度T之间的曲线关系；(b)1%Er³⁺单掺杂样品在980 nm上转换激发下Ln(R)与1/T之间的线性关系；(c)1%Er³⁺单掺杂样品在980 nm上转换激发下测温灵敏度S与绝对温度T之间的曲线关系；(d)1%Yb³⁺/1%Er³⁺共掺杂样品在980 nm上转换激发下的荧光强度比R与绝对温度T之间的曲线关系；(e)1%Yb³⁺/1%Er³⁺共掺杂样品在980 nm上转换激发下Ln(R)与1/T之间的线性关系；(f)1%Yb³⁺/1%Er³⁺共掺杂样品在980 nm上转换激发下测温灵敏度S与绝对温度T之间的曲线关系

Figure 4.(a)Relationship betweenRand absolute temperatureTof 1%Er³⁺-doped sample under 980 nm(UC) excitation; (b)Monolog plot ofRas a function of reciprocal absolute temperature of 1%Er³⁺-doped sample under 980 nm(UC) excitation; (c)Sensor sensitivity(S) as a function of the absolute temperature of 1%Er³⁺-doped sample under 980 nm(UC) excitation; (d)Relationship betweenRand absolute temperatureTof 1%Yb³⁺/1%Er³⁺co-doped sample under 980 nm(UC) excitation; (e)Monolog plot ofRas a function of reciprocal absolute temperature of 1%Yb³⁺/1%Er³⁺co-doped sample under 980 nm(UC) excitation; (f)Sensor sensitivity(S) as a function of absolute temperature of 1%Yb³⁺/1%Er³⁺co-doped sample under 980 nm(UC) excitation

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图 5(a) 1%Er³⁺单掺杂样品的X射线激发下转换发射谱；(b)1%Yb³⁺/1%Er³⁺共掺杂样品的X射线激发下转换发射谱

Figure 5.(a)DC emission spectrum of 1%Er³⁺-doped sample excited with X-ray; (b)DC emission spectrum of 1%Yb³⁺/1%Er³⁺co-doped sample excited with X-ray

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图 6(a) 1%Er³⁺单掺杂样品处于不同温度(303 K, 433 K and 563 K)时的X射线激发下转换发射谱；(b)1%Yb³⁺/1%Er³⁺共掺杂样品处于不同温度(303 K, 433 K and 563 K)时的X射线激发下转换发射谱。图中均对552 nm处的峰进行了归一化

Figure 6.(a)DC spectra of 1%Er³⁺-doped sample at different temperatures(303 K, 433 K and 563 K) excited with X-ray; (b)DC spectra of 1%Yb³⁺/1%Er³⁺co-doped sample at different temperatures(303 K, 433 K and 563 K) excited with X-ray. The spectra were normalized at 552 nm

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图 7(a) 1%Er³⁺单掺杂样品在X射线下转换激发下的荧光强度比R与绝对温度T之间的曲线关系；(b)1%Er³⁺单掺杂样品在X射线下转换激发下Ln(R)与1/T之间的线性关系；(c)1%Er³⁺单掺杂样品在X射线下转换激发下测温灵敏度S与绝对温度T之间的曲线关系；(d)1%Yb³⁺/1%Er³⁺共掺杂样品在X射线下转换激发下的荧光强度比R与绝对温度T之间的曲线关系；(e)1%Yb³⁺/1%Er³⁺共掺杂样品在X射线下转换激发下Ln(R)与1/T之间的线性关系；(f)1%Yb³⁺/1%Er³⁺共掺杂样品在X射线下转换激发下测温灵敏度S与绝对温度T之间的曲线关系

Figure 7.(a)Relationship betweenRand absolute temperatureTof 1%Er³⁺-doped sample under X-ray(DC) excitation; (b)monolog plot ofRas a function of reciprocal absolute temperatureTof 1%Er³⁺-doped sample under X-ray(DC) excitation; (c)sensor sensitivity(S) as a function of absolute temperature of 1%Er³⁺-doped sample under X-ray(DC) excitation; (d)relationship betweenRand absolute temperatureTof 1%Yb³⁺/1%Er³⁺co-doped sample under X-ray(DC) excitation; (e)monolog plot ofRas a function of reciprocal absolute temperature of 1%Yb³⁺/1%Er³⁺co-doped sample under X-ray(DC) excitation; (f)sensor sensitivity(S) as a function of the absolute temperature of 1%Yb³⁺/1%Er³⁺co-doped sample under X-ray(DC) excitation

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图 8(a)x%Yb³⁺/1%Er³⁺(x=1, 5, 10, 15, 20)共掺杂样品在X射线下转换激发下的荧光强度比R与绝对温度T之间的曲线关系；(b)x%Yb³⁺/1%Er³⁺(x=1, 5, 10, 15, 20)共掺杂样品在X射线下转换激发下测温灵敏度S与绝对温度T之间的曲线关系

Figure 8.(a)Relationship betweenRand absolute temperatureTofx%Yb³⁺/1%Er³⁺(x=1, 5, 10, 15, 20) co-doped samples under X-ray(DC) excitation; (b)sensor sensitivity(S) as a function of absolute temperature forx%Yb³⁺/1%Er³⁺(x=1, 5, 10, 15, 20) co-doped samples under X-ray(DC) excitation

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表 1Er³⁺在不同Yb³⁺/Er³⁺共掺基质中的最高测温灵敏度和计算荧光强度比中涉及到的参数B和ΔE/k_B的大小，及每种材料达到最高测温灵敏度时所需温度和激发波长

Table 1.The fluorescence intensity ratio parameters and values of the maximum sensitivity of Er³⁺in different Yb³⁺/Er³⁺co-doped hosts, and temperatures for the maximum sensitivity as well as the excitation wavelength

Host	B	ΔE/k_B(K)	S_MAX(K^-1)	T/K	Excitation wavelength/nm	Ref.
NaZnPO₄	12.8	1 218.4	0.005 7	612	980	28
Ba₂LaF₇	1.56	396.88	0.004 3	298	980	29
CaF₂	6.79	1 263.6	0.003 1	625	980	30
KLu₂F₇	10.86	1 242	0.004 7	620	980	31
La₂(WO₄)₃	18.12	1 018.39	0.009 7	510	980	18
NaY(WO₄)₂	29.2	1 073.6	0.014 5	530	980	19
NaLa(MO₄)₂	24.78	1 035	0.013 1	510	980	32
NaYF₄	4.89	1 117.4	0.002 4	560	980	33
GdF₃	3	1 127	0.004	575	980	34
NaGdF₄	7.71	1 135	0.003 7	580	980	35
silicate glass	3.65	592.6	0.003 3	286	978	36
Yttrium silicate powders	3.65	817	0.005 6	400	975	37
NaGd(WO₄)₂	27.11	1 178.32	0.034 46	539	X-ray	本文

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