摘要
本文研究了不同波长激发下YVO4∶1％Er3+的荧光测温特性.在312和345 nm照射 下,测量了 YVO4∶1％Er3+的变温激发光谱和发射光谱.结果表明,在303～573 K范围内,随着温度的增加,在312 nm激发下,Er3+离子的2H11/2→4I15/2发射增强,2S3/2→4I15/2发射减弱;在345 nm激发下,Er3+离子的2H11/2→4I15/2发射增强,2S3/2→4I15/2发射也增强.我们认为在312 nm激发下,随温度的变化,Er3+的2H11/2→4I15/2发射增强和2S3/2→4I15/2发射减弱来源于稀土离子热布居效应和基质的吸收减弱;在345 nm激发下,Er3+的2H11/2→4I15/2发射和2S3/2→4I15/2发射同时增强来源于基质和稀土离子的基态热布居效应.通过拟合2H11/2和2S3/2两个能级的能级差,得到ΔE312=650.94cm-1,ΔE345=674.36cm-1,这样的结果也说明不同的激发可以实现相反的荧光强度变化趋势,但并不影响两能级间粒了数的玻尔兹曼分布.
Abstract
The fluorescence temperature sensing characteristics of YVO4∶1％Er3+excited under different wave-lengths have been investigated.The variable-temperature excitation and emission spectra of YVO4∶1％Er3+were measured excited at 312 and 345 nm.The results indicate that,in the temperature range of 303-573 K,an in-crease in temperature leads to an enhancement of the Er3+ion's 2H11/2 to 4I15/2 emission and a weakening of the 2S3/2 to 4I15/2 emission under 312 nm excitation.Conversely,under 345 nm excitation,both the 2H11/2 to 4I15/2 and the 2S3/2 to 4I15/2 emissions are enhanced.It is postulated that the observed changes in emission under 312 nm ex-citation with temperature are due to the thermal population effect of the rare-earth ions and the reduced absorp-tion by the matrix;while under 345 nm excitation,the simultaneous enhancement of both emissions is attribut-ed to the thermal population effects of the matrix and the ground state of the rare-earth ions.By fitting the ener-gy level difference between the 2H11/2 and 2S3/2 levels,the values of ΔE312=650.94 cm-1 and ΔE345=674.36 cm-1 are obtained.These results also demonstrate that different excitation wavelengths can lead to opposite trends in fluo-rescence intensity changes,yet do not affect the Boltzmann distribution of particle numbers between the thermal-ly coupled energy levels.
基金项目
黑龙江省教育厅基本科研业务费创新团队项目(KYYWF10236190301)
黑龙江省教育厅基本科研业务费青年项目(KYY-WF10236190102)
黑龙江省教育厅基本科研业务费青年项目(KYYWF10236190106)
NETL
NSTL
万方数据