Stepwise Crosslinking: A Facile Yet Versatile Conceptual Strategy to Nanomorphology‐Persistent Porous Organic Polymers

Both high surface areas and well‐orchestrated nanomorphologies are important for porous organic polymers (POPs). However, the two key characteristics are generally difficult to be satisfied simultaneously, because the common pore‐making procedures usually produce ill‐defined nanomorphologies or give rise to damage of precustomized nanomorphologies. Herein, a facile yet versatile stepwise crosslinking strategy for fabrication of POPs with an unusual nanomorphology‐persistent characteristic during pore‐making is reported. Polystyrene nanofibers and poly(styrene‐co‐divinylbenzene) nanosphere arrays are utilized as building blocks, and then transformed into nanofibrillar morphology‐persistent and ordered array morphology‐persistent POPs via stepwise crosslinking, respectively. The stepwise crosslinking strategy includes pre‐crosslinking and hypercrosslinking; the pre‐crosslinking in a carefully selected poor solvent of polystyrene forms a lowly crosslinked structure, which guarantees the stability of nanomorphology during the subsequent pore‐making via hypercrosslinking. The as‐obtained POPs can be used as precursors for novel well‐defined hyperporous carbon nanofibers and ordered carbon nanosphere arrays with excellent adsorption performances.