Researchers first to link silicon atoms on surfaces

Nanowerk  March 30, 2021 Researchers in Germany have demonstrated Si–Si bond formation on Au(111) and Cu(111) surfaces by using two different monomers, each containing two silicon functional groups (CH3SiH2 or SiH3) attached to an aromatic backbone, leading to polymeric disilenes that interact with the surface. A combination of experimental and theoretical studies corroborated the formation of covalent Si–Si bonds between the long, highly ordered polymer chains with high diastereoselectivity. The reactive Si=Si bonds formally generated via double dehydrogenative coupling were stabilized via covalent Si–surface interaction. This method could be used to develop a completely new strategy for molecular changes to […]

Wafer-thin nanopaper changes from firm to soft at the touch of a button

Science Daily  March 24, 2021 Mimicking the sea cucumbers which adapt and strengthen their tissue so that their soft exterior immediately stiffens when attacked by predators, researchers in Germany have developed a mechanism to strengthen and stiffen a material using electric current. They developed cellulose nanofibrils/polymer nanopapers with tailor-made interactions by deposition of thin single-walled carbon nanotube electrode layers for Joule heating. Application of DC at specific voltages translates into significant electrothermal softening via dynamization and breakage of the thermo-reversible supramolecular bonds. The altered mechanical properties are reversibly switchable in power on/power off cycles. Currently a power source is needed […]