【摘要】 为了提高上转换材料在激光防伪领域的绿光发射强度,采用高温固相法制备Ba²⁺、Al³⁺、Sr²⁺掺杂YF₃∶Ho³⁺,Yb³⁺材料。通过980 nm近红外激发的上转换发射光谱,可知Ba²⁺、Al³⁺、Sr²⁺的掺杂都会使得晶格收缩,降低稀土离子周围晶体场的对称性,其546 nm绿光强度分别是未掺杂该金属离子样品的1.6倍、1.1倍、1.2倍。并根据X射线衍射（XRD）探究Ba²⁺含量对晶相的作用。通过差热分析（DTA）、上转换发射光谱、XRD、扫描电子显微镜（SEM）,结果表明:对于最佳Ba²⁺、Al³⁺、Sr²⁺掺杂含量但不同烧结温度的样品,当合成温度为940℃时发光性能、结晶度和晶粒生长较好。通过发射强度与激发电流的拟合结果,说明546 nm绿光是双光子吸收过程,并阐述980 nm激发YF₃∶Ho³⁺,Yb³⁺发光材料的能级跃迁过程。更多还原

【Abstract】 Upconversion materials of YF₃∶ Ho³⁺,Yb³⁺doped with Ba²⁺,Al³⁺,Sr²⁺were prepared by high temperature solid state method in order to enhance green emission intensities in the field of laser anti-counterfeit. Ba²⁺,Al³⁺and Sr²⁺could cause lattice shrinking,reduce crystal field symmetry around rare earth ions. The 546 nm green emission intensities of samples doped with Ba²⁺,Al³⁺,Sr²⁺were 1.6,1. 1,1. 2 times as strong as the ones without the metal ions respectively according to upconversion emission spectra under 980 nm near-infrared excitation. The Ba²⁺contents had effects on crystal phases with X-ray diffraction（XRD）. The results of Differential Thermal Analysis（DTA）, upconversion emission spectra,XRD,Scanning Electron Microscope（SEM） showed that optimal sintering temperature was 940 ℃ where optimal luminescence properties,crystallinities,grain growth appeared for samples with the optimal Ba²⁺,Al³⁺,Sr²⁺doping content but different sintering temperatures. 546 nm green emission was two-photon absorption process with fitting results of emission intensity and excitation current. Energy level transition processes were represented for YF₃∶ Ho³⁺,Yb³⁺luminescent materials under 980 nm excitation.更多还原