Metal-containing polymers as molecular nanowires
The term polymer typically brings to mind the variety of plastics used to make beverage bottles, yogurt containers and the like. However, a polymer is simply a long chain of a single type of subunit, the monomers of which the final molecule is composed. A slight variation is imposed in the use of a few different monomers that, when forming a chain, yield an oligomer. Metal-containing polymers, or metallopolymers, have become the focus of widespread interest due to the combination of processing advantages of polymers and functionalities provided by incorporation of metals. Applications include sensors, light-emitting devices, solar cells and catalysis reactions. One important obstacle to widespread use of metallopolymers has been difficulties in synthesis; proven polymerisation protocols for organic polymers yielded relatively insoluble and poorly characterised metallopolymers. European researchers sought to synthesise M-M–bonded oligomeric or polymeric linear metal chain complexes with EU funding of the SPIM project. Linear chain complexes could have important application as novel molecular nanowires. In addition to synthesising and characterising a variety of compounds, the team discovered self-assembly capabilities of certain materials. This property was explored for its potential to produce conductive and emissive nanowires for use in nano-scale electronic and optoelectronic devices. The SPIM team also extended work to evaluate cylindrical structures in addition to linear ones for use as catalytic platforms in synthetic chemistry. SPIM project advances regarding functional metallopolymer-based nanostructures should have important impact in applications including organic field-effect transistors, solar cells and light-emitting diodes.
