Nd3+掺杂的NaYF4∶Yb@NaYF4∶Ho上转换纳米颗粒的光谱分析

摘要

上转换纳米颗粒因具有良好的穿透深度和发光强度被广泛地应用在生物标记或生物成像中.实验制备了核壳结构的NaYF4∶Yb@NaYF4∶Ho纳米颗粒,分散均匀,粒径在50 nm左右.通过光谱分析可知,该纳米颗粒可在980 nm激光激发下发射波长为650 nm为主的发射光.进一步对该核壳结构的NaYF4∶Yb@NaYF4∶Ho纳米颗粒进行Nd3+掺杂,制备了可被800 nm激光激发且发射强红光的纳米颗粒.通过比较多种不同结构的Nd3+掺杂NaYF4∶Yb@NaYF4∶Ho纳米颗粒的荧光光谱发现,NaYF4∶Yb@NaYF4∶Ho,Nd纳米颗粒发射光最强,表明Nd3+掺杂在NaYF4∶Yb@NaYF4∶Ho纳米颗粒的壳层中最佳.最后对NaYF4∶yb3+50％@NaYF4∶Ho3+ 1％,Nd3+x％纳米颗粒Nd3+离子的掺杂浓度进行优化,实验结果表明:Nd3+掺杂浓度为30％时,该纳米颗粒在800 nm激光激发下发光强度最强.%Upconversion nanoparticles are widely used in bioimaging and biomarkers because of their excellent penetration depth and strong luminescence.Mono dispersed core-shell structured NaYF4∶Yb@NaYF4∶Ho nanoparticles with sizes of about 50 nm were synthesized.It was found by spectral analysis that these nanoparticles emitted light centered at a wavelength of 650 nm under the 980 nm laser excitation.Further Nd3+ doping caused the NaYF4∶Yb@NaYF4∶Ho nanoparticles to emit strong red light under the 800 nm laser excitation.By analyzing the fluorescence spectra of the Nd3+ doped NaYF4∶Yb@NaYF4∶Ho nanoparticles with different structures,it was found that the emission intensity of the NaYF4∶Yb@NaYF4∶Ho,Nd nanoparticles was the strongest,indicating that doping Nd3+ ions into the shell layer of the NaYF4∶Yb@NaYF4∶Ho nanoparticles was optimal choice.Finally,the Nd3+ concentration of the NaYF4∶Yb3+50％@NaYF4∶Ho3+1％,Nd3+x％ nanopartiCles was optimized.The experimental results show that the optimized concentration of Nd3+ ions is 30％,the luminescence intensity of the NaYF4∶ yb3+50％@NaYF4∶Ho3+1％,Nd3+30％ nanoparticles is strongest under an 800 nm laser excitation.