N-Doped porous graphitic carbon with multi-flaky shell hollow structure prepared using a green and ‘useful’ template of CaCO3 for VOC fast adsorption and small peptide enrichment

High N-doped porous graphitic carbons (S-NPGCs) with multi-flaky shell hollow structure were prepared by using CaCO3 as a green/useful template. S-NPGCs exhibit very fast adsorption for toluene (31 times that of HKUST-1) and effectively selective enrichment of small peptides with high inhibitory activity of angiotensin converting enzymes.