A Material Viewpoint on Metal-Backboned Polymers

Creating polymers with novel backbone compositions is key to achieving materials with novel functionalities. Recently, the incorporation of continuous metal-metal bonds into the backbones of a novel class of metal-backboned polymers (MBPs), distinct from both conventional nonmetallic polymers and coordination polymers with discrete metal centers, has opened a new direction in materials science. In this Perspective, it introduces the concept of MBPs and then outline promising synthetic strategies for their preparation. Special emphasis is placed on elucidating how extended metal-metal bonding within the backbone imparts distinctive optical, electrochemical, magnetic, and electrical properties to these polymers. After that, applications are discussed in areas such as microwave absorption and thermoelectric materials, as well as emerging opportunities in molecular electronics, energy harvesting, catalysis, and fiber electronics. Finally, it outline critical challenges and propose future research directions to fully unlock the potential of MBPs.