Nitrogen‐Doped Carbon Materials Prepared from Polyurethane Foams

N‐doped carbon materials were prepared from polyurethane foams (PUFs) with glutaric dialdehyde under hydrothermal and carbonization processes. Glutaric dialdehyde could preserve morphology and nitrogen‐containing groups of the PUFs, and promoted the aromatization of the resultant carbon materials. The rich of nitrogen content endowed it having high selectivity for CO 2 capture from air.