Design and preparation of porous carbons from conjugated polymer precursors

Porous nanostructured carbon materials exhibit unique structural features such as high surface area and excellent physicochemical stability and have been of significantly scientific and technological interest because of their vital importance in many energy related applications. Synthetic polymers represent a major class of precursors for developing cutting-edge porous carbons, among which conjugated polymers have emerged as an attractive family of carbon precursors. Distinct from those typical polymer precursors, the robust conjugated structure ensures sufficient framework carbonizability and nanoarchitecture-conserving stability during carbonization process, which is crucial to the successful transformation of designed polymer architectures to finally desired carbon nanostructures. Moreover, heteroatom doping (e.g., N, S, B, and metals) or codoping can be naturally integrated into carbon framework directly by using the heteroatom-containing monomers. Especially, using the newly emerged structurally defined carbon-rich conjugated porous networks as precursors, precise control of compositions and structures of carbon materials becomes possible even at the molecular level. In this review, we will highlight recent strategies to the preparation of porous carbon materials with well-defined porous nanostructures using conjugated polymers as versatile precursors. Beginning with a brief introduction to these precursors, including linear-type conjugated polymers and conjugated porous networks, the synthetic techniques for the fabrication of porous nanostructured carbons by direct templating, self-assembly, template-free, chemical activation, and microwave irritation approaches, will be reviewed. Meanwhile, the sophisticated nanomorphologies, precisely controlled porous structures, and custom-designed functionalities of these conjugated-structure-derived carbons, together made them amenable to diverse task-specific applications, such as electrocatalysis, Li-ion batteries, supercapacitors, and adsorption. Finally, a perspective of the research directions in this field will be presented.