Open AccessMechanofluorochromism of a Difluoroboron-β-Diketonate Derivative at the Nanoscale
Author(s) -
Marine Louis,
Cristian Piñero García,
Arnaud Brosseau,
Clémence Allain,
Rémi Métivier
Publication year - 2019
Publication title -
the journal of physical chemistry letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.563
H-Index - 203
ISSN - 1948-7185
DOI - 10.1021/acs.jpclett.9b01923
Subject(s) - nanoscopic scale , materials science , nanoparticle , phase transition , atomic force microscopy , hypsochromic shift , grinding , nanotechnology , chemical engineering , fluorescence , composite material , optics , physics , engineering , quantum mechanics
Mechanofluorochromic nanoparticles have been prepared from a difluoroboron β-diketonate complex, and their behavior has been investigated at the nanoscale using atomic force microscopy (AFM) coupled with fluorescence spectroscopy. Two types of nanoparticles were observed, associated with green and yellow emission, reflecting the crystalline polymorphism of this material. While the green-emitting nanoparticles are mechanically insensitive under our conditions, the yellow-emitting ones display a marked hypsochromic shift upon shearing with the AFM tip. At the macroscopic level, the grinding of the bulk material is attributed to the amorphization of the crystalline powder. On the contrary, the marked mechanofluorochromism observed at the nanoscale is attributed to a crystal-to-crystal phase transition. This specific behavior at the nanolevel is extremely promising for applications such as nanoprobes of local mechanical stress.