First publication from my new position in Barcelona !
The amazing etching of zeolite-like MOFs into various shapes achieved by my colleagues Civan and Xavi has just been accepted for publication in Angewandte Chemie, one of the best scientific journal for research in general chemistry.
About the paper: Controlling the shape of metal–organic framework
(MOF) crystals is important for understanding their crystallization
and useful for myriad applications. However, despite
the many advances in shaping of inorganic nanoparticles, postsynthetic
shape control of MOFs and, in general, molecular
crystals remains embryonic. Herein, we report using a simple
wet-chemistry process at room temperature to control the
anisotropic etching of colloidal ZIF-8 and ZIF-67 crystals. Our
work enables uniform reshaping of these porous materials into
unprecedented morphologies, including cubic and tetrahedral
crystals, and even hollow boxes, by an acid–base reaction and
subsequent sequestration of leached metal ions. Etching tests
on these ZIFs reveal that etching occurs preferentially in the
crystallographic directions richer in metal–ligand bonds; that,
along these directions, the etching rate tends to be faster on the
crystal surfaces of higher dimensionality; and that the etching
can be modulated by adjusting the pH of the etchant solution.