A dual emission metal–organic framework for rapid ratiometric fluorescence detection of CO(3)(2−) in seawater

A dual emission metal–organic framework (IRMOF-10-Eu) was prepared and used as a ratiometric fluorescent sensor for CO(3)(2−) detection. IRMOF-10-Eu had good stability and excellent luminescence in aqueous solution. IRMOF-10-Eu showed dual fluorescence emission from the ligand and Eu(3+) with single excitation. Upon treatment with CO(3)(2−), the fluorescence ratio (I(624)/I(358)) of the probe displayed significant change. The relative fluorescence intensity ratio (I(624)/I(358)) and CO(3)(2−) concentration had a linear relationship in 50–300 μM range with a low detection limit of 9.58 μM. And the luminescence probe of CO(3)(2−) showed a fast detection time. The possible mechanism was investigated. CO(3)(2−) changed the structure of IRMOF-10-Eu and interrupted the energy transfer process. Thus, the fluorescence emission intensity of the ligand was increased and Eu(3+) was decreased with the addition of CO(3)(2−). IRMOF-10-Eu was used to detect CO(3)(2−) in seawater, which showed good prospect in practical application. Subsequently, a highly selective and sensitive probe, IRMOF-10-Eu, may pave an efficient way for CO(3)(2−) detection in seawater.