In this work, N/O codoped porous carbons (NOPCs) were derived from corn silk accompanied by Na2CO3 activation. The structures and surface chemical features of as-prepared carbon materials tailored adjusting the mass ratio. After activation, optimized sample (NOPC1) with abundant ultramicropores pyrrolic N displays an enhanced CO2 adsorption capacity 3.15 mmol g−1 1.95 at 273 K 298 1 bar, respec...