5 years ago

Dual-emitting fluorescence of Eu/Zr-MOF for ratiometric sensing formaldehyde

Dual-emitting fluorescence of Eu/Zr-MOF for ratiometric sensing formaldehyde
A dual-emitting luminescent lanthanide/transition heterometal-organic frameworks of Eu/Zr-MOF was synthesized by incorporation of Eu3+ ions into NH2-UiO-66 under microwave irradiation condition. The multiband fluorescence derived from the characteristic emission of Eu3+ and linker-to-cluster (Eu- oxo or Zr- oxo) charge transfer (LCCT) transition was fabricated. By combination of the luminescent property with the intrinsic porosity and open sites of amine group to bind target analytes, the Eu/Zr-MOF exhibited small molecules-dependent luminescence enhancement and quench effects. Notably, a drastic enhancement of fluorescent at 465nm induced by formaldehyde was observed. Thus, a ratiometric fluorescent sensing for formaldehyde was performed based on the intensity ratio of two emission bands at 465 and 615nm for Eu/Zr-MOF. Under the excitation of 365nm, the increase in intensity ratio of the two emission bands was nearly linearly proportional to the amount of formaldehyde. By this Eu/Zr-MOF sensor, the detection limit of formaldehyde was 0.2mg/L. This sensing mechanism was ascribed to the binding interaction of free amino groups in Eu/Zr-MOF with the guest. An added electron transfer from amino group containing lone pair electrons to the positively charged formaldehyde leads to a drastic enhancement of luminescence at about 465nm, while the characteristic emission of Eu3+ at 615nm enhances slightly. These studies demonstrate that the strategy of multiband emissive heterometal-MOFs can be served as a facile method to fabricate sensitive and specific fluorescent probes of polluting organic small molecules.

Publisher URL: www.sciencedirect.com/science

DOI: S0925400517310857

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.