Metal-Interrupted Perylene Diimide: Toward a New Class of Tunable n-Type Inorganic−Organic Hybrid Semiconductors

Abstract

In organic thin-film transistors (OTFTs), organic electron-transport materials (n-type semiconductors) are well behind the advances in development of hole-transport materials (p-type semiconductors). Currently, one class of organic n-type semiconductor materials that is widely utilized is N,N'-dialkyl-3,4,9,10-perylenetetracarboxylic diimide (PTCDI-R) derivatives with high electron affinities (EAs), such as N,N'-dioctyl-3,4,9,10-perylenetetracarboxylic diimide with a reported EA as high as 4.4 eV. The PTCDI-R derivatives have been manipulated by adding substituents on the perylene moiety or at the amine position to afford more stable compounds and higher EAs. On the basis of these materials, we have developed metal-containing perylenediimide analogues, placing a salpen ligand for metal ion chelation between two n-isobutylnaphthalimides. We demonstrate here that the electronic properties of this class of materials can be systematically tuned in a divergent manner by simply changing the metal center. The synthesis, characterization, electrochemistry, and band-gap analysis are discussed herein.