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So far, a number of methods have been used to arrive at creating nanomaterials. However, scientists have not been able to weave them. Researchers from the Lawrence Berkeley National Laboratory have now woven the first three-dimensional covalent organic frameworks (COFs) from helical organic threads. These have a number of advantages as far as "structural flexibility, resiliency and reversibility" are concerned, compared to earlier COFs.

"We have taken the art of weaving into the atomic and molecular level, giving us a powerful new way of manipulating matter with incredible precision in order to achieve unique and valuable mechanical properties," Omar Yaghi, one of the researchers, said in a press release.

Being porous and three-dimensional crystals, the COFs have huge internal surface areas. This makes them store a lot of targeted molecules. They were stitched together into massive networks that stuck together by chemical bonds by the inventor of COFs, Yaghi.

"Weaving in chemistry has been long sought after and is unknown in biology. However, we have found a way of weaving organic threads that enable us to design and make complex two- and three-dimensional organic extended structures."

Yaghi's team took a copper (I) complex as the foundation in order to weave the organic compound "phenanthroline," leading to the creation of a network of immines labelled COF0505. It led to the realisation that X-ray and electron diffractions can amend the copper ion structure, restoring it to its original state.

"That our system can switch between two states of elasticity reversibly by a simple operation, the first such demonstration in an extended chemical structure means that cycling between these states can be done repeatedly without degrading or altering the structure," Yaghi said. "Based on these results, it is easy to imagine the creation of molecular cloths that combine unusual resiliency, strength, flexibility and chemical variability in one material."

The study was published in the Jan. 22,2016 issue of Science.