Abstract Eu(btc) metal organic frameworks (MOFs) were prepared by co-precipitation method via 1,2,4-benzenetricarboxylic acids (H3btc) connecting with Eu3+ ions, and the morphology was controlled from compact spherical to irregular honeycomb by adjusting the pH of reaction solutions. The luminescence properties of Eu(btc) MOFs were found related to the surface morphology of products, and the compact spherical one performed stronger emission intensity. The sensing ability of Eu(btc) MOFs to 11 kinds of metal ions was investigated and a prominent quenching effect occurred in Fe3+, Cr3+ or Ni2+ solutions. Base on UV-vis absorption analysis, an “Ion-fence” model presented the competition to absorb exciting light between Eu(btc) MOFs and adsorbed metal ions. Based on Stern-Volmer equation, the Eu(btc) detection was found with higher Ksv value and a lower detection limit. Meanwhile, a higher sensing efficiency was confirmed in the Eu(btc) MOFs with loose honeycomb due to aggravating porous surface offering much more sites for metal ions.

中文翻译：

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荧光Eu(btc)金属有机骨架对金属离子检测能力的表面效应

摘要 以 1,2,4-苯三羧酸 (H3btc) 与 Eu3+ 离子连接共沉淀法制备 Eu(btc) 金属有机骨架材料 (MOFs)，通过调节 pH 控制其形貌由致密球形变为不规则蜂窝状。反应溶液。发现 Eu(btc) MOFs 的发光特性与产品的表面形态有关，紧凑的球形结构具有更强的发射强度。研究了 Eu(btc) MOFs 对 11 种金属离子的传感能力，在 Fe3+、Cr3+ 或 Ni2+ 溶液中出现了显着的淬火效应。基于紫外-可见吸收分析，“离子栅栏”模型展示了 Eu(btc) MOFs 和吸附金属离子之间吸收激发光的竞争。基于 Stern-Volmer 方程，发现 Eu(btc) 检测具有较高的 Ksv 值和较低的检测限。同时，由于加剧的多孔表面为金属离子提供了更多的位置，因此在具有松散蜂窝的 Eu(btc) MOF 中证实了更高的传感效率。