Chen Wei, Kong Shu, Wang Jian, Du Liping, Cai Wen, Wu Chunsheng
Institute of Medical Engineering, Department of Biophysics, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University Xi'an 710061 China
RSC Adv. 2019 Jan 28;9(7):3734-3739. doi: 10.1039/c8ra10330e. eCollection 2019 Jan 25.
A novel graphitic carbon nitride (g-CN)@ZIF-8 nanocomposite was synthesized by a facile approach and applied as a fluorescent sensor. The fluorescent quenching and enhancing effect of g-CN@ZIF-8 nanocomposite was explored for potential applications in sensing metal ions and solvents based on photoluminescence (PL) measurements. Compared with g-CN nanosheets alone, the combined g-CN@ZIF-8 nanostructure greatly improved the sensitivity for the detection of metal ions due to the special fluorescent quenching effect. In particular, the sensitivities of the detection of Cu and Ag improve from 29.1 to 11.2 ppm and from 40 to 16.5 ppm, respectively, which were significantly improved compared to that of g-CN nanosheets alone. The sensitivity could increase about 100% and 250% for Cu and Ag by the g-CN@ZIF-8. The limit of detection (LOD) for Cu and Ag by g-CN@ZIF-8 was 11.2 ppm and 13.2 ppm, respectively. Both g-CN nanosheets and g-CN@ZIF-8 nanocomposite can be used for distinguishing Fe and Fe in solutions. The LOD of Fe by g-CN@ZIF-8 was as low as 65.4 ppm. On the other hand, the relative increased luminescence of g-CN@ZIF-8 to the g-CN in tetrahydrofuran (THF) was selective, which was successfully applied for detecting this specific solvent. An excellent linear relationship (0-1.0 v/v of THF/water) between the THF fraction and PL intensities was obtained. These results demonstrate that the g-CN@ZIF-8 nanocomposite provide a convenient and novel approach for the enhance fluorescence detection of metal ions and distinguishing of specific solvents.
通过一种简便的方法合成了一种新型的石墨相氮化碳（g-CN）@ZIF-8纳米复合材料，并将其用作荧光传感器。基于光致发光（PL）测量，探索了g-CN@ZIF-8纳米复合材料的荧光猝灭和增强效应在金属离子和溶剂传感方面的潜在应用。与单独的g-CN纳米片相比，复合的g-CN@ZIF-8纳米结构由于特殊的荧光猝灭效应，大大提高了检测金属离子的灵敏度。特别是，检测Cu和Ag的灵敏度分别从29.1 ppm提高到11.2 ppm以及从40 ppm提高到16.5 ppm，与单独的g-CN纳米片相比有显著提高。通过g-CN@ZIF-8检测Cu和Ag的灵敏度可分别提高约100%和250%。g-CN@ZIF-8对Cu和Ag的检测限分别为11.2 ppm和13.2 ppm。g-CN纳米片和g-CN@ZIF-8纳米复合材料均可用于区分溶液中的Fe²⁺和Fe³⁺。g-CN@ZIF-8对Fe²⁺的检测限低至65.4 ppm。另一方面，g-CN@ZIF-8相对于g-CN在四氢呋喃（THF）中的相对发光增强具有选择性，已成功应用于检测这种特定溶剂。在THF分数与PL强度之间获得了良好的线性关系（THF/水为0 - 1.0 v/v）。这些结果表明，g-CN@ZIF-8纳米复合材料为增强金属离子的荧光检测和区分特定溶剂提供了一种便捷新颖的方法。
