Synthesis and Luminescence Performances of Macroporous Ca12Al14O32Cl2:Tb3+ Monoliths for Ag+ Fluorescence Sensor

Macroporous terbium-doped Ca12Al14O32Cl2 (C12A7:Tb3+) monoliths have been synthesized via a sol-gel route, and the macroporous structure, luminescence performances and detection of Ag+ in water of the C12A7:Tb3+ monoliths were investigated in detail. The introduction of Tb element has an important role on the macroporous structure of C12A7 monoliths, and the macropore size gradually decreases with the increase of Tb doping concentration. The luminescence intensity of 3% Tb-doped C12A7 monolith reaches the maximum, and the corresponding macropore size is close to 0.6 μm and the porosity is about 70.4%. High luminescence intensity of Tb-doped C12A7 monolith is attributed to higher scattering light and wonderful high temperature stability dervied from the resultant macrostructure. The luminescence decay of Tb3+ is determined to the local environment in macroporous C12A7 monoliths, and the maximum luminous life can reach 2584.24 μs in the local environment closer to O2-. The obtained macroporous C12A7:Tb3+ material has a sensitive response to Ag+, and can become a promising fluorescence sensor for the detection of Ag+.

通过溶胶-凝胶法合成了大孔掺铽Ca12Al14O32Cl2（C12A7:Tb³+）整体块体材料，并对该材料的大孔结构、发光性能以及其用于水中银离子检测的性能开展了详细研究。铽元素的引入对C12A7整体块体的大孔结构具有重要调控作用，且大孔孔径随铽掺杂浓度的升高逐渐减小。3%掺铽C12A7整体块体的发光强度达到峰值，其对应的大孔孔径约为0.6 μm，孔隙率约为70.4%。掺铽C12A7整体块体的高发光强度源于其大孔结构所赋予的更强光散射效应与优异的高温稳定性。Tb³+的发光衰减特性由大孔C12A7整体块体的局域环境决定，在更接近O²-的局域环境中，其最大发光寿命可达2584.24 μs。所制备的大孔C12A7:Tb³+材料对Ag+具有灵敏响应，有望成为用于检测Ag+的高性能荧光传感器。