3 years ago

Polymorphism, Mechanofluorochromism, and Photophysical Characterization of a Carbonyl Substituted Difluoroboron-β-Diketone Derivative

Polymorphism, Mechanofluorochromism, and Photophysical Characterization of a Carbonyl Substituted Difluoroboron-β-Diketone Derivative
Rémi Métivier, Arnaud Brosseau, Marine Louis, Clémence Allain, Fuyuki Ito, Régis Guillot
Difluoroboron-β-diketones are known to exhibit very promising mechanochromic luminescence but a greater understanding of these materials and their mechanoresponsive properties is still desirable. Here we demonstrate that a combination of spectroscopic and physicochemical techniques is necessary to understand the variation of solid-state fluorescence observed under mechanical stress and thermal annealing. For this study, we decided to focus on a new fluorescent compound showing a polymorphic behavior. Our investigation on the mechanofluorochromic properties is based on a thorough spectroscopic study (steady-state and time-resolved) on powder samples and thin films deposited on paper and coverglass substrates. Three different states were identified: two crystalline states (a stable green-emissive and a metastable yellow-emissive one) and an amorphous phase (yellow orange emission). The detailed photophysical properties highlight the dynamic excimer formation processes, which can take place in the yellow-emissive crystalline and amorphous states, along with the effect of the substrate on the thin films composition. These results were confirmed by studying the thermal annealing process with a combined AFM and fluorescence microscope. The switching between these states under mechanical and thermal treatments underlies the fluorescence color changes.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b01901

DOI: 10.1021/acs.jpcc.7b01901

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.