Recently, the reporter learned from Shanghai Jiaotong University that Wang Shiyong, a special researcher at the School of Physics and Astronomy, collaborated with scientists from Switzerland, Germany and the United States to synthesize graphene nanoribbons with topological properties for the first time. Related results were recently published in the journal Nature.
In physics, topology is a substance Basic properties. Topological materials have novel physical properties not found in traditional materials. For example, the conductive edges of such materials are protected by the intrinsic nature of the material, and can often exhibit the conductive properties regardless of the presence of defects. Therefore, it can be used to design non-dissipative electronic devices, which has great application prospects. Wang Shiyong told the Journal of the Chinese Academy of Sciences that they first prepared one-dimensional graphene nanoribbons with topological properties and detected the topological properties of graphene materials.
Graphene nanoribbons are quasi-one-dimensional graphene nanostructures. Due to quantum confinement effects and boundary effects, their electronic structures are closely related to the width and edge structure. Although theoretical studies have shown that graphene nanoribbons can exhibit a series of singular electrical, magnetic, and topological properties, so far only a few theoretical predictions have been confirmed by deterministic experiments.
Based on the “bottom-up” surface synthesis pathway, researchers have achieved precise atomic-scale graphene by selecting different molecular precursors to achieve precise regulation of the width, shape, and doping of nanostructures. Nano-structure. The ultra-high resolution AFM imaging technique determines the chemical structure of the synthesized nanobelts and verifies that the relevant synthesis methods are highly controllable. The scanning tunnel differential spectroscopy technique determines the topological properties of graphene nanoribbons, and the correlation results are highly consistent with the theory.
At the same time, Chinese and foreign scientists have accurately designed the molecular precursors to achieve precise regulation of topological properties, and synthesized graphene nanoribbons with alternating topologically uniform widths on the surface of Au(111) and observed them. Topological end states to the ends of graphene nanoribbons.
This work was highly recognized by reviewers of Nature magazine: “This work is highly original and exciting, and has great significance in different fields.”
Related paper information: Nature 560, 209-213, 2018
Source: Science Network
2018 China International Graphene Innovation Conference