Metal Organic Frameworks (MOFs) are highly porous crystalline solids comprised of inorganic, secondary building units (SBUs) and organic ligands.  MOFs are of interest for use in a multitude of applications, including gas capture, storage, drug delivery, and catalysis.  Post-synthetic exchange (PSE) is one method of modifying the organic or metal components of preformed MOF nanoparticles following synthesis in order to incorporate additional functionality or to control surface chemistry.  Typically, PSE is performed in a solution of chemically distinct but related ligand, and PSE time and temperature are adjusted to achieve the desired degree of incoming ligand incorporation.  Herein, we utilize ball-milling as a physical means to achieve PSE, measuring bulk levels of ligand using energy-dispersive X-ray spectroscopy (EDX).  Exchange amount varied, depending on ball-milling conditions such as energy.  Surface exchange was also explored as a function of ball-milling energy using X-ray photoelectron spectroscopy (XPS).  These findings also demonstrate the feasibility of using ball-milling as a more environmentally friendly method of PSE in comparison to traditional methods.

Post-synthetic exchange in UiO-66 via ball-milling

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.