【作者】 刘英；

【导师】 孙立忠；

【作者基本信息】 湘潭大学 ， 材料科学与工程， 2022， 硕士

【摘要】 随着科技的发展,光纤通讯、近红外光谱检测等应用领域对近红外发光材料的需求日益增长,特别是高效超宽波段近红外发光材料成为了限制这些领域发展的瓶颈。Bi,Cr掺杂材料具有良好的宽带近红外发光性能,因而获得广泛关注。Bi掺杂玻璃可通过选择合理基质玻璃与掺杂调控,实现1000-1700 nm波段的超宽带近红外发光,但Bi掺杂近红外发光玻璃的发光效率低下,限制了该类材料的发展。本文利用碳增强Bi宽带近红外发光,再利用Yb³⁺/Cr³⁺共掺来拓宽其近红外发光,并将其作为近红外光源在酒精浓度检测方面做出了尝试。考虑到Bi掺杂玻璃的发光强度仍不够高,导致在近红外光谱检测中的光信号不足,选择Cr³⁺掺杂Li Sc Si O₄荧光粉实现了超宽带近红外发光,并利用Li Sc_0.97Si O₄:0.03Cr³⁺荧光粉作为光源在近红外光谱检测方面作了应用尝试,具体内容如下:1、制备了Bi掺杂宽带近红外发光玻璃,其发光中心波长为1160 nm,半高宽为160 nm。在玻璃样品中通过引入碳可以显著提高Bi掺杂硼酸盐玻璃的宽带近红外发射强度,其宽带近红外发射源于Bi⁺。物相分析表明,碳的加入并没有改变这些掺Bi硼酸盐玻璃的微观结构,这表明碳还原效应可以显著增加Bi的近红外发光中心。在有还原剂的情况下,Bi₂O₃的最佳掺杂浓度为0.06 mol%左右。为了进一步拓宽Bi掺杂玻璃的近红外发射带,通过Bi与Cr³⁺/Yb³⁺共掺,使Bi掺杂玻璃近红外光谱半高宽得到一定程度的展宽。最后利用这种玻璃作为近红外光源,在近红外光谱检测方面做了初步应用尝试。2、制备了LiSc_1-xSi O₄:x Cr³⁺宽带近红外荧光粉,在450 nm光源激发下,其发光范围为1000 nm到1700 nm,发光中心位于1220 nm左右,光谱半高宽约为250 nm。Li Sc_1-xSi O₄:x Cr³⁺荧光粉在蓝光区域有较好的吸收,宽带近红外发射源于Cr³⁺离子的自旋允许的⁴T₂（F）→⁴A₂（F）跃迁。随着Cr³⁺离子掺杂浓度的增加,Li Sc_1-xSi O₄:x Cr³⁺荧光粉的近红外发射强度逐渐增加,当Cr³⁺离子掺杂浓度为0.03时,荧光粉的近红外发光强度达到峰值。最后利用Li Sc_0.97Si O₄:0.03Cr³⁺荧光粉作为近红外光源,在近红外光谱检测方面（乙醇汽油含量检测、酒精浓度检测）做了初步应用尝试,其线性相关系数分别为0.9881和0.9947,表明Li Sc_1-xSi O₄:x Cr³⁺宽带近红外荧光粉在近红外光谱检测方面具有潜在的应用前景。更多还原

【Abstract】 With the development of science and technology,the demand for near-infrared luminescent materials in the application fields of optical fiber communication and infrared spectrum detection is increasing.In particular,high-efficiency ultra-broadband near-infrared luminescent materials have become the bottleneck restricting the development of these fields.Bi,Cr doped materials have good broadband near-infrared luminescence properties,so they have attracted extensive attention.Bi doped glass can achieve ultra-broadband near-infrared luminescence in 1000-1700 nm band by selecting reasonable matrix glass and doping regulation,but the low luminous efficiency of Bi doped near-infrared luminescence glass limits the development of this kind of materials.In this paper,carbon-enhanced Bi broadband near-infrared luminescence was used,and then Yb³⁺/Cr³⁺co-doping was used to broaden its near-infrared luminescence,and it was used as a near-infrared light source in alcohol concentration detection.Considering that the luminescence intensity of Bi doped glass is still not high enough,resulting in insufficient optical signal in the detection of near-infrared spectroscopy,Cr³⁺doped Li Sc Si O₄ phosphors were selected to achieve ultra-broadband near-infrared luminescence.An attempt was made to use Li Sc_0.97Si O₄:0.03Cr³⁺phosphor as a light source in near-infrared spectral detection.The specific contents are as follows:1.The Bi doped broadband near-infrared luminescent glasses were prepared with a central wavelength of 1160 nm and a half-width of 160 nm.The broadband near-infrared emission intensity of Bi-doped borate glass can be significantly enhanced by introducing carbon into glass samples,and its broadband near-infrared emission originates from Bi⁺.Phase analysis showed that the addition of carbon did not change the microstructure of these Bi-doped borate glasses,which indicated that the carbon reduction effect could significantly increase the near-infrared luminescence centers of Bi.In the presence of reducing agent,the optimal doping concentration of Bi₂O₃ is about 0.06 mol%.In order to further broaden the near-infrared emission band of Bi-doped glass,the near-infrared spectral half-width of Bi-doped glass is broadened to a certain extent by co-doping Bi and Cr³⁺/Yb³⁺.Finally,the glass is used as a near-infrared light source,and a preliminary application attempt is made in the near-infrared spectrum detection.2.Li Sc_1-xSi O₄:x Cr³⁺broadband near-infrared phosphors have been prepared.Under the excitation of 450 nm light source,the luminescence range is from 1000 nm to 1700 nm,the luminescence center is around 1220 nm,and the full width at half maximum is about 250 nm.Li Sc_1-xSi O₄:x Cr³⁺phosphors have good absorption in the blue light region,and the broadband near-infrared luminescence originates from the⁴T₂（F）→⁴A₂（F）transition allowed by the spin of Cr³⁺ions.With the increase of Cr³⁺ion doping concentration,the near-infrared luminescence intensity of Li Sc_1-xSi O₄:x Cr³⁺phosphors gradually increased.When the Cr³⁺ion doping concentration was 0.03,the near-infrared luminescence intensity of the phosphors reached a peak value.Finally,the Li Sc_0.97Si O₄:0.03Cr³⁺phosphor is used as the near-infrared light source,and a preliminary application attempt is made in the near-infrared spectrum detection（ethanol gasoline content detection,alcohol concentration detection）,and the linear correlation coefficients were 0.9881 and 0.9947,respectively.It shows that Li Sc_1-xSi O₄:x Cr³⁺broadband near-infrared phosphors have potential application prospects in near-infrared spectral detection.更多还原