Self-assembling materials discovered
6 Feb 2017 by Evoluted New Media
Researchers at the Academy of Finland have discovered gold nanoclusters that can self-assemble to form two and three-dimensional materials
Researchers at the Academy of Finland have discovered gold nanoclusters that can self-assemble to form two and three-dimensional materials.
The nanoclusters used in the study contained 102 gold atoms and 44 thiol molecules. The self-assembly process occurred in a water-methanol mixture.
Professor Hannu Häkkinen, from the Academy of Finland and who co-ordinated the research, said: “In biology, typical examples of self-assembling functional systems are viruses and vesicles. Biological self-assembled structures can also be de-assembled by gentle changes in the surrounding biochemical conditions. It’ll be of great interest to see whether these gold-based materials can be de-assembled and then re-assembled to different structures by changing something in the chemistry of the surrounding solvent.”
The thiol surface on the gold nanocluster has a large number of acidic groups that form hydrogen bonds with neighbouring nanoclusters - initiating self-assembly. One structure formed was a two-dimension hexagonally ordered layer of stacked nanocluster layers. When researchers adjusted the synthesis conditions, three-dimensional hollow capsid structures were seen. Both structures were one nanocluster thick - either in the form of layers or capsid walls.
Researchers believe that next-gen functional materials could be created from the two-dimensional nanosheets. “The free-standing two-dimensional nanosheets will bring opportunities towards new-generation functional materials, and the hollow capsids will pave the way for highly lightweight colloidal framework materials,” said postdoctoral researcher Nonappa, from Aalto University.
The research was published in Angewandte Chemie.
