Liquid-phase bottom-up synthesis of graphene nanoribbons

Graphene nanoribbons (GNRs) - an emerging family of carbon-based semiconductors - can be precisely synthesised from small molecules such as benzene derivatives through bottom-up approaches. This review outlines a summary of the development of bottom-up synthesis of GNRs in liquid phase. The strategies are classified based on edge structures and widths of the materials, which are the crucial factors for properties of GNRs. In addition, views on challenges in the field and the future outlook are also provided.