A highly fluorescent post-modified metal organic framework probe for selective, reversible and rapid carbon dioxide detection.

The monitoring of the arterial and exhaled CO 2 is of great importance. Despite of many reports on metal organic frameworks (MOFs) in adsorbing and separating CO 2 , the application of fluorescent MOFs probes for CO 2 detection was rarely reported. A new fluorescent MOF probe UIO-66-ONa for CO 2 detection was developed via post-synthesis of UIO-66-NH 2 through a Schiff base reaction with salicylaldehyde and further treatment with sodium hydroxide. This probe exhibited a remarkable fluorescence color change from green to blue and showed excellent sensitivity and selectivity for CO 2 sensing in solution. The detection limit was as low as 3.5 × 10−7 M. The excellent sensing performance of UIO-66-ONa was ascribed to the efficient reaction between sodium phenolic group and CO 2 , which led to the transformation of UIO-66-ONa to UIO-66-OH as evidenced by the emission spectra. This post-synthetic modification idea provided a new strategy for designing fluorescent MOFs probes for CO 2 detection. A new fluorescent metal organic framework probe (UIO-66-ONa) exhibits the excellent sensing performance towards CO 2 detection as the interaction between sodium phenolic group and CO 2 , the detection limit is 3.5 × 10−7 M. Image 1 • A new fluorescent MOF probe (UIO-66-ONa) for CO2 detection was developed via post-synthesis of UIO-66-NH2. • UIO-66-ONa exhibits excellent selectivity, sensitivity and reusability for CO2 detection in solution. • A promising design strategy for the synthesis of high efficient fluorescent MOFs for gas sensing. [ABSTRACT FROM AUTHOR]