Dutta Joydip, Chakraborty Mitesh, Rai Vineet Kumar
Central Research Facility, Indian Institute of Technology (Indian School of Mines) Dhanbad 826004 Jharkhand India.
Department of Physics, St. Xavier's College Ranchi 834001 Jharkhand India
RSC Adv. 2023 Aug 4;13(34):23386-23395. doi: 10.1039/d3ra03238h.
Tm; Yb:ZnTiO samples have been synthesized using a solid state reaction route. The phase, lattice parameters, crystallite size has been examined using X-ray Diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). An intense peak of Yb codoped samples is observed near ∼957 nm due to the F → F transition in diffuse reflectance spectra (DRS), which confirms the presence of Yb ion in the prepared compound. The optical band gap of Yb codoped samples has been calculated using Kubelka-Munk function. The Raman spectra corresponds to incorporation of Tm/Yb at the octahedral and tetrahedral site of the spinel host. The emission spectra recorded by using 370 nm excitation wavelength shows intense blue colour band corresponding to the G → H transition of Tm ion. The upconversion (UC) emission spectra recorded by using 980 nm laser excitation source shows emission bands due to the G → H, G → F and H → H transitions of Tm ion in the host matrix lying in the blue, red and NIR regions respectively. There is effective enhancement of about ∼35 times in the blue UC emission intensity with incorporation of Yb at 3% doping concentration in the prepared sample. The anti-counterfeit application of the optimized upconverting phosphor has been successfully demonstrated.
铥镱共掺的钛酸锌样品通过固态反应路线合成。利用X射线衍射（XRD）和高分辨率透射电子显微镜（HRTEM）对其相、晶格参数和微晶尺寸进行了研究。在漫反射光谱（DRS）中，由于F→F跃迁，在约957nm处观察到铥镱共掺样品的一个强峰，这证实了所制备化合物中存在镱离子。利用库贝尔卡-蒙克函数计算了铥镱共掺样品的光学带隙。拉曼光谱表明铥/镱掺入到了尖晶石基质的八面体和四面体位置。使用370nm激发波长记录的发射光谱显示出对应于铥离子G→H跃迁的强蓝色带。使用980nm激光激发源记录的上转换（UC）发射光谱显示出分别位于蓝色、红色和近红外区域的发射带，这归因于基质中铥离子的G→H、G→F和H→H跃迁。在制备的样品中掺入3%掺杂浓度的镱时，蓝色上转换发射强度有效增强了约35倍。成功展示了优化后的上转换荧光粉的防伪应用。
