Li Xueyuan, Li Qintang, Lei Nana, Chen Xiao
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan 250100, China.
State Key Laboratory of Environmental Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China.
ACS Omega. 2019 Jan 31;4(1):2437-2444. doi: 10.1021/acsomega.8b03555.
Hydrogels based on bile salts and lanthanide ions have been reported for their easy gelation. However, the weak mechanical properties and water quenching to luminescence of lanthanide ions limit their applications in practice. Hence, a supramolecular ionogel has been prepared here through simply mixing of sodium deoxycholate and europium nitrate in a protic ionic liquid, ethylammonium nitrate (EAN). The prepared ionogel was characterized by scanning electron microscopy, X-ray energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, fluorescence spectroscopy, and rheological measurements. Such an ionogel resulted synergistically from metal coordination and hydrogen bonding. The effect of the solvent structure on gel properties was also explored by comparison with those formed in alkylammonium nitrates with longer chains. EAN was found to behave more effectively both as a solvent and a bridge to enhance the ionogel mechanical strength. The ionogels also exhibited better fluorescent properties than those of the corresponding hydrogels. The obtained results should expand the applications of lanthanide-containing luminescent soft materials in nonaqueous media. It is expected to apply in the fields of solid electrolytes, biosensors, and optics response.
基于胆盐和镧系离子的水凝胶因其易于凝胶化而被报道。然而，镧系离子的机械性能较弱以及对发光的水猝灭限制了它们在实际中的应用。因此，通过在质子离子液体硝酸乙铵（EAN）中简单混合脱氧胆酸钠和硝酸铕，制备了一种超分子离子凝胶。通过扫描电子显微镜、X射线能量色散光谱、傅里叶变换红外光谱、X射线粉末衍射、荧光光谱和流变学测量对制备的离子凝胶进行了表征。这种离子凝胶是由金属配位和氢键协同作用产生的。还通过与在具有较长链的烷基硝酸铵中形成的凝胶进行比较，探索了溶剂结构对凝胶性质的影响。发现EAN作为溶剂和增强离子凝胶机械强度的桥梁表现得更有效。离子凝胶也比相应的水凝胶表现出更好的荧光性质。所得结果应扩展含镧系发光软材料在非水介质中的应用。有望应用于固体电解质、生物传感器和光学响应等领域。
