Metallo-Organic Thin Films Made in Israel

We demonstrate controlled charge trapping and release, accompanied by multiple color changes in metallo-organic coatings. The dual functionality of our metallo-organic materials provides fundamental insight into metal-mediated electron transport pathways. The electrochemical processes are accompanied by distinct, color-to-color transitions. Some of our coatings consist of two elements: 1) a nanoscale gate consisting of a layer of well-defined polypyridyl ruthenium complexes bound to a flexible transparent electrode, and 2) a charge storage layer consisting of isostructural iron complexes attached to the surface of the gate. This gate mediates or blocks electron transport in response to an applied voltage. Combining electrochemistry with optical data revealed mechanistic information: the coloration of the coatings directly relates to the formation of intermediate species, providing evidence for catalytic positive charge release mediated through the gate. These and other coatings can be functional elements in conventional electronic circuits.