Controllable Synthesis Of Nitrogen Doped Porous Carbon For CO₂ Capture

Nitrogen doped porous carbon material is a carbon based composite material with nitrogen atom (nitrogen containing functional group) as reinforcing material, the pore structure, electrochemical properties of porous carbon materials can be improved by nitrogen doping. Nitrogen sources (contained nitrogen precursor) have an important influence on the nitrogen content, the location and the chemical environment of the carbon materials, therefore, the selection of suitable nitrogen source is a prerequisite for the synthesis of high performance porous carbon materials. In this paper, Poly (4-vinylpyridine) (P4VP) was used as carbon and nitrogen source to prepare of nitrogen doped porous carbon materials based on metal-organic coordination structure. The main work and conclusions are as follows:(1) Nitrogen doped porous carbon (NDPC) was prepared based on Fe-P4VP coordination structure by using P4VP as carbon nitrogen source and FeCl3 6 H2O as auxiliary. P4VP will completely decompose even in an inert atmosphere, but under the coordination and catalysis of Fe3+, it can be converted to carbon at very low temperature(400 ?). The aggregation of iron nanoclusters in the carbonization process showed different pore-forming methods at different temperatures. The as-prepared materials possess high specific surface area (up to 1211 m2g-1), large pore volume (up to 0.96 cm3g-1), narrow microporosity and high N content (up to 9.9 wt%). Due to these unique features, the materials show high CO2 uptake capacity and excellent selectivity for CO2/N2 separation. The CO2 uptake capacity of NDPC-2-600 are up to 6.8 and 4.3 mmolg-1 at 0 and 25?; the CO2/N2 (0.15/0.85) selectivity at 0 and 25 ? also reach 18.4 and 15.2, respectively.(2) On the basis of Fe3+ coordination/catalysis to make P4VP be carbonized, the samples with larger surface area and more porous structure were obtained by activation;The effects of different activators and different activation methods on the pore structure of the material were studied, NH3, CO2, H2O and KOH were selected as activators. The results showed that the concentration of pore size distribution and specific surface area of NDPC-2-600 samples decreased with the activation of NH3 and CO2, the specific surface area of NDPC1211-NH3 and NDPC1211-CO2 were 1206 and 1129 m2g-1,respectively; H2O and KOH were activated to obtain samples with larger specific surface area, the specific surface area of NDPC-H2O and NDPC-KOH-6112-700 samples reached 1352 and 1402 m2g-1,respectively.