▎ 摘　　要

Graphene nanoribbons (GNRs) are the ribbons of graphene with a width of nanoscale. According to the different edge configurations, the GNRs can be classified into Zigzag-edge graphene nanoribbons (ZGNRs) and Armchair-edge graphene nanoribbons (AGNRs), strongly affecting electronic structure and properties of GNRs. The triggered quantum confinement and edge effects by rationalizing the structural design can open the bandgap of GNRs. Besides, GNRs have huge length-to-width ratio and proportion of edge atoms, which provide infinite possibilities for realizing functional customization through structure tailoring. These geometric and electronic structural properties make graphene nanoribbons have more application potential than graphene in many fields such as electronic devices. Therefore, the related research of graphene nanoribbons has been a hot spot in the field of nanomaterials. This review introduces the structures and properties of graphene nanoribbons firstly, and then provides a comprehensive picture of the preparation approaches of GNRs, and the corresponding preparation methods can be divided into two parts: (1) Top-down categories: The GNRs are obtained by the etching and cutting of graphene, as well as carbon nanotubes (CNTs), with utilizing the plasma, ion beam, scanning tunneling microscope and metal nanoparticles. However, these methods are still in the stage of laboratory research, and fabrication of high quality GNRs is difficult because of lacking the processing accuracy. (2) Bottom-up categories: The GNRs can be synthesized using carbon containing precursors, e.g. organic compounds, hydrocarbon gas and SiC. The bottom-up method facilitates to prepare several nanometers-width GNRs with a certain degree of controllability, among which ultra-narrow GNRs can be fabricated using organic synthesis, and the chemical vapor deposition (CVD) method is expected to achieve the industrial production of high-quality GNRs with low-cost preparation. Finally, we discuss the challenges and prospects of the research of GNRs. We believe that GNRs will become a new structural and functional material with great application potential in numerous fields, as is catalyzed by innovative development of materials and techniques.