Speaker
James Armstrong
Speaker's Institution
Colorado State University
Date
10/16/20
Time
4:00 PM
Location
Virtual Research Seminar
Additional Information

Coinage metal-thiolate assemblies exemplify hierarchical structure and structure-property relationships.  They comprise structurally weak hydrogels of stacked sheets.  Inclusion of an anti-solvent in synthesis of these materials fundamentally changes their structure, resulting instead in colloidal amorphous metal complexes. The colloids undergo a hydration-dependent and reversible sol-gel transition.  Because the colloids are flexible, they morph in the sol-gel transition to eliminate void spaces, producing a surprisingly rigid gel.  Sodium ions that are aqueous in the sol transition to bridge colloids in the gel, rigidifying the system.  The underlying structure results in a material that is strikingly disparate from compositionally similar materials. The distinct rheological properties that emerge that may render coinage metal-thiolate assemblies as engineering-grade materials.