Gao Peng, Liu Quanxiao, Wu Jiao, Jing Jun, Zhang Wenguan, Zhang Junying, Jiang Tao, Wang Jigang, Qi Yuansheng, Li Zhenjun
Beijing Key Laboratory of Printing and Packaging Materials and Technology, Beijing Institute of Graphic Communication, Beijing 102600, China.
School of Physics, Beihang University, Beijing 100191, China.
Nanomaterials (Basel). 2023 Jul 9;13(14):2034. doi: 10.3390/nano13142034.
A series of long-afterglow luminescent materials (SrAlO: Eu (SAOE), SrAlO: Eu, Dy (SAOED) and SrAlO: Eu, Dy, Gd (SAOEDG)) was synthesized via the combustion method. Temperature and concentration control experiments were conducted on these materials to determine the optimal reaction temperature and ion doping concentration for each sample. The crystal structure and luminescent properties were analyzed via X-ray diffraction (XRD), photoluminescence (PL), and afterglow attenuation curves. The outcomes demonstrate that the kind of crystal structure and the location of the emission peak were unaffected by the addition of ions. The addition of Eu to the matrix's lattice caused a broad green emission with a central wavelength of 508 nm, which was attributed to the characteristic 4f5d to 4f electronic dipole, which allowed the transition of Eu ions. While acting as sensitizers, Dy and Gd could produce holes to create a trap energy level, which served as an electron trap center to catch some of the electrons produced by the excitation of Eu but did not itself emit light. After excitation ceased, this allowed them to gently transition to the ground state to produce long-afterglow luminescence. It was observed that with the addition of sensitizer ions, the luminous intensity of the sample increased, and the afterglow duration lengthened. The elemental structure and valence states of the doped ions were determined with an X-ray photoelectron spectrometer (XPS). Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the samples. The results show that the sample was synthesized successfully, and the type and content of ions in the fluorescent powder could be determined. The fluorescence lifetime, quantum yield, bandgap value, afterglow decay time, and coordinate position in the coherent infrared energy (CIE) diagram of the three best sample groups were then analyzed and compared. Combining the prepared phosphor with ink provides a new idea and method for the field of anti-counterfeiting through screen printing.
通过燃烧法合成了一系列长余辉发光材料（SrAlO:Eu（SAOE）、SrAlO:Eu,Dy（SAOED）和SrAlO:Eu,Dy,Gd（SAOEDG））。对这些材料进行了温度和浓度控制实验，以确定每个样品的最佳反应温度和离子掺杂浓度。通过X射线衍射（XRD）、光致发光（PL）和余辉衰减曲线分析了晶体结构和发光性能。结果表明，离子的添加不影响晶体结构类型和发射峰位置。向基质晶格中添加Eu会产生中心波长为508nm的宽绿色发射，这归因于Eu离子的特征4f5d到4f电子偶极跃迁。Dy和Gd作为敏化剂时，会产生空穴以形成陷阱能级，作为电子陷阱中心捕获Eu激发产生的部分电子，但自身不发光。激发停止后，这使得它们能够缓慢跃迁到基态产生长余辉发光。观察到随着敏化剂离子的添加，样品的发光强度增加，余辉持续时间延长。用X射线光电子能谱仪（XPS）确定了掺杂离子的元素结构和价态。使用扫描电子显微镜（SEM）和能量色散X射线光谱（EDX）对样品进行表征。结果表明样品成功合成，并且可以确定荧光粉中离子的类型和含量。然后对三个最佳样品组的荧光寿命、量子产率、带隙值、余辉衰减时间以及在相干红外能量（CIE）图中的坐标位置进行了分析和比较。将制备的荧光粉与油墨结合为丝网印刷防伪领域提供了新的思路和方法。
