Study On Preparation And Optical Thermosensitivity Of Rare-earth Doped Oxide Glass Ceramics Containing Oxide Nanocrystalline

Temperature detection is often involved in the application fields for instance industry,daily life,husbandry and scientific and technological disquisition.With the elaboration of contemporary lore and technology and stricter requisition of utilization,we also put forward the higher and more stringent requirement for the accuracy of temperature detection and harsher environment of utilization.Traditional contact temperature detection method has been incompetent to redeem the sine qua non requiring a high-tech utilization in different scenarios and environments for instance nanometer measuring range,high-speed operation,extreme pressure and strong electromagnetic field,etc.Therefore,it is necessary to search for and explore the non-contact temperature detection technology which has the vantage of escalated sensitivity,elevated precision and rapid response.In recent years,the non-contact temperature detection technology based on the optical response properties of materials has attracted the attention of many researchers.The temperature-sensitive properties of rare-earth ion doped fluorescent materials have been deeply explored to meet the different utilization needs of various domains in contemporary society.We have investigated the current both domestic and abroad research status of fluorescence temperature detection technology through a large number of articles review.We will deeply discuss the urgent problems of fluorescent thermo-sensitive materials to make the development prospects of fluorescent thermo-sensitive materials better.Our investigated outcomes are presented as below:According to the problems found in the latest research papers,we developed a series of different high-performance glass-ceramics with different compositions based on the principle of temperature detection and the exploration of new materials.We kept trying a new temperature measuring mechanism and optimizing the temperature measuring method,and finally,we got the glass-ceramics with excellent sensitivity.According to our research results,our glass-ceramic material is promising to be universally utilized in the domains of optical fibre temperature sensing.Based on the exploration of a new temperature detection mechanism,we optimized the temperature detection method,and finally we obtained the glass-ceramics with excellent sensitivity.Tb³⁺/Pr³⁺co-doped transparent glass-ceramics containing Ba Mo O₄nanocrystals were successfully synthesized by using high-temperature melt quenching and further heat treatment.And we use the instruments to characterize and analyze its structure and performance.After studying the temperature-dependent properties of the glass-ceramic samples by using the new thermometry mechanism,our experimental results show that the excitation spectra of the transparent glass-ceramic samples have a wide envelope between 250-300 nm due to the charge transfer transition of Pr³⁺/Tb³⁺-Mo⁶⁺.Under 266 nm excitation,the luminescence intensity of Tb³⁺:⁵D₄→⁷F₅（543 nm）and Pr³⁺:³P₁→³H₅（527 nm）shows an opposite temperature dependence.The former has less temperature dependence due to thermal quenching,while the latter has more temperature dependence because the ³P₁ and ³P₀ of Pr³⁺belong to the thermally coupled level.Due to the opposite temperature-dependent luminescence characteristics of the two samples,we used the fluorescence intensity ratio of our samples to conduct temperature detection,and the results of temperature detection obtained a better sensitivity.We predict that this temperature measuring mechanism can be applied to fibre optic temperature sensors.We developed a novel glass-ceramics material and selected the most popular temperature measuring mechanism to study the temperature-sensitive characteristics of the samples.Through a continuous exploration of sample composition ratio and preparation conditions,we finally synthesized glass-ceramic samples containing Ca₈Tb₂（PO₄）₆O₂ nanocrystals.The samples were characterized by differential scanning calorimetry,X-ray diffraction,transmission spectrum and high-resolution transmission electron microscopy.To improve the sensitivity of glass-ceramic samples,we choose the low excited state heat occupation method to test the temperature sensitivity of the samples.We have analyzed the dependence of excitation and emission spectra of Ca₈Tb₂（PO₄）₆O₂ nanocrystalline glass-ceramics with temperature variation,and obtained the expected high sensitivity performance.The next step is to develop its application in optical fibre temperature sensing.Based on the previous phase,we synthesized glass-ceramics samples containing Ca₈Sm₂（PO₄）₆O₂ nanocrystals by adjusting the composition of glass-ceramics materials and studied the samples with two different temperature measuring mechanisms,and finally got glass-ceramics with excellent sensitivity.Firstly,the temperature sensing properties of Ca₈Sm₂（PO₄）₆O₂ nanocrystalline glass-ceramics were studied after analyzing the dependence of excitation and emission spectrum on temperature based on the low excited state heat occupation technology of Sm³⁺ions.The dependence of the fluorescence intensity ratio of ⁴G_5/2→⁶H_7/2 and ⁴G_7/2→⁶H_7/2 emission peak of Sm³⁺on temperature was analyzed based on the temperature measurement technique of triple energy cascade of Sm³⁺ions.Based on the research results,we have carried out temperature detection and obtained good sensitivity.It shows that our material has potential application in the field of the optical fibre temperature sensor.