Cicconi Maria Rita, Deng Hongyi, Otsuka Takahito, Telakula Mahesh Aadhitya, Khansur Neamul Hayet, Hayakawa Tomokatsu, de Ligny Dominique
Department of Materials Science and Engineering, Institut für Glas und Keramik, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Nagoya 466-8555, Japan.
Materials (Basel). 2024 May 11;17(10):2283. doi: 10.3390/ma17102283.
In this study, the photoluminescence (PL) behavior of two aluminosilicate glass series containing alkali-niobates ranging from 0.4 to 20 mol% was investigated. The glasses exhibit an intense visible emission centered at 18,400 cm for the peralkaline series and at higher energies (19,300 cm) for the metaluminous glasses. However, the photoluminescence emission intensity varies significantly with the niobate content and the bulk chemistry. PL and fluorescence lifetime measurements indicate that the broad emission bands result from the overlap of different niobate populations, whose distribution changes with niobate content. The distinct PL behavior in the two glass series was related to the structural evolution of the niobate units upon niobium addition. An enhancement of the visible emission was observed for a higher fraction of distorted [NbO] units. Eu-doping was carried out as a structural probe of the glass network, and also to determine if these glasses could be used as potential rare earth element (REE) activators. The crystal field strength around Eu ions is strongly dependent on the bulk chemistry and the niobate content. Furthermore, the peralkaline series showed energy transfer from the host [NbO] to Eu, confirming the feasibility of exploring niobate glasses and glass-ceramics as lanthanide ion-activated luminescent materials. In addition, glass-ceramics (GCs) containing alkali-niobate phases with a perovskite-like structure were developed and studied to verify the optical performance of these materials. It was verified that the bulk chemistry influences crystallization behavior, and also the photoluminescence response. The transparent GC from the metaluminous series exhibits a quenching of the Eu emission, whereas an enhanced emission intensity is observed for the peralkaline GC. The latter shows a strong excitation-dependent PL emission, suggesting energy transfer and migration of electronic excitation from one Eu population to another. Additionally, Eu emissions arising from the D15 and D25 excited states were observed, highlighting the low phonon energy achievable in niobo-aluminosilicate hosts.
在本研究中，对两个含有0.4至20摩尔％碱金属铌酸盐的铝硅酸盐玻璃系列的光致发光（PL）行为进行了研究。对于过碱性系列玻璃，其在18,400 cm处呈现出强烈的可见发射峰，而对于准铝质玻璃，则在更高能量（19,300 cm）处出现发射峰。然而，光致发光发射强度随铌酸盐含量和整体化学组成而显著变化。PL和荧光寿命测量表明，宽发射带是由不同铌酸盐群体的重叠所致，其分布随铌酸盐含量而变化。两个玻璃系列中不同的PL行为与添加铌后铌酸盐单元的结构演变有关。对于更高比例的畸变[NbO]单元，观察到可见发射增强。进行了Eu掺杂，作为玻璃网络的结构探针，同时也用于确定这些玻璃是否可作为潜在的稀土元素（REE）激活剂。Eu离子周围的晶体场强度强烈依赖于整体化学组成和铌酸盐含量。此外，过碱性系列显示出从主体[NbO]到Eu的能量转移，证实了探索铌酸盐玻璃和玻璃陶瓷作为镧系离子激活发光材料的可行性。此外，开发并研究了含有具有钙钛矿结构的碱金属铌酸盐相的玻璃陶瓷（GCs），以验证这些材料的光学性能。已证实整体化学组成影响结晶行为以及光致发光响应。准铝质系列的透明GC显示出Eu发射的猝灭，而过碱性GC则观察到发射强度增强。后者显示出强烈的激发依赖型PL发射，表明能量转移以及电子激发从一个Eu群体迁移到另一个群体。此外，观察到来自D15和D25激发态的Eu发射，突出了铌铝硅酸盐主体中可实现的低声子能量。
