Synthesis　of　carbon　materials　with　both　large　surface　area　and　abundant　heteroatoms　is　an　important　task　in　scientific　research.　Traditional　approaches　mostly　proceed　at　extremely　high　temperature,　and　suffer　from　complex　routes　and/or　expensive　raw　materials.　NaNH2　has　been　recently　found　to　be　able　to　not　only　etch　C　atoms　to　create　nanochannels,　but　also　substitute　O　species　to　introduce　N　species.　In　this　work,　an　effective　approach　to　N-doped　porous　carbons　was　realized　by　treating　hydrothermal　carbons　(HTCs)　with　sodium　amide　(NaNH2).　The　considerable　amount　of　O　species　preserved　in　pristine　HTCs　enables　the　achievement　in　simultaneous　activation　and　N-doping　of　HTCs　by　NaNH2　at　relatively　moderate　temperature　(400-600).　The　porous　and　chemical　structure　of　NaNH2-treated　HTCs　were　characterized　systematically.　Although　the　pristine　HTCs　are　almost　non-porous　and　N-free,　the　specific　surface　areas　and　total　N　contents　of　prepared　NaNH2-treated　HTCs　reach　190-2430m2/g　and　0.78-6.57　wt.%　respectively.　Furthermore,　the　CO2　capture　performance　of　NaNH2-treated　HTCs　was　also　examined　considering　their　highly　porous　and　N-doped　nature.　Interestingly,　NaNH2-treated　HTCs　exhibit　high　CO2　capacities,　large　CO2/N2　selectivities,　fast　CO2　adsorption　rate　and　excellent　recyclability,　endowing　them　with　potential　application　as　solid　adsorbents　for　CO2　capture.　©　2019　Elsevier　Ltd.