On-Surface Synthesis on Nonmetallic Substrates
Kewei Sun, Yuan Fang, Lifeng Chi
Abstract
On-surface synthesis has been developed into a promising research field for fabricating low-dimensional materials with great potential in tailoring structures, functionality, and, thus, desired chemical and physical properties. Thus far, most surface-assisted reactions are conducted on single-crystal metal surfaces, which serve as catalysts. However, the metal surface severely quenches the intrinsic electronic or optical properties of the adsorbed functional material. In view of potential applications, in particular device fabrication, direct integration of functional molecular systems on technologically relevant insulating or semiconducting surfaces is highly desirable. Recently, significant efforts have been made toward realizing chemical reactions on nonmetallic substrates; however, details of their catalytic mechanisms are still unclear and require further investigation. On the other hand, various approaches have been demonstrated to replace the catalytic functionality of metals with, for example, photochemistry or direct tip manipulation. In this Perspective, we review early advances in this field of nonmetallic surface confined reactions and highlight upcoming opportunities and challenges. We start by describing recent advances in reaction types, followed by presenting various external catalytic methods and end with pointing out promising future directions.