Iron Nanoclusters as Template/Activator for the Synthesis of Nitrogen Doped Porous Carbon and Its CO₂ Adsorption Application

Abstract

We propose a facile synthesis approach for nitrogen doped porous carbon and demonstrate a novel pore-forming method that iron nanoclusters act as a template or activator at different carbonization temperatures based on Fe-poly(4-vinyipyridine) (P4VP) coordination. P4VP will completely decompose even in an inert atmosphere, but under the coordination and catalysis of Fe, it can be converted to carbon at a very low temperature (400 °C). 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 m g), large pore volume (up to 0.96 cm g), narrow microporosity, and high N content (up to 9.9 wt %). Due to these unique features, the materials show high CO uptake capacity and excellent selectivity for CO/N separation. The CO uptake capacity of NDPC-2-600 is up to 6.8 and 4.3 mmol g at 0 and 25 °C; the CO/N (0.15/0.85) selectivity at 0 and 25 °C also reaches 18.4 and 15.2, respectively.

Enhanced N-doped Porous Carbon Derived from KOH-Activated Waste Wool: A Promising Material for Selective Adsorption of CO2/CH4 and CH4/N2

“…The band at about 1580 cm −1 represents N–H in-plane deformation vibration or C=C stretching vibration in aromatic rings [42,43]. The characteristic absorption at 1418 cm −1 corresponded to C–N stretching vibration [44]. The broad band around 1200–1000 cm −1 can be assigned to the C–N or C–O stretching vibration [41,42].…”

“…The corresponding N species are presented in Figure 4b. The peaks at ~398.1 eV, ~400.0 eV, ~400.7 eV, and ~402.8 eV are attributed to pyridinic-N (N-6), pyrrolic-/pyridonic-N (N-5), quaternary-N (N-Q), and N-oxides of pyridine (N-x), respectively [43,44,46,47,48]. The structure of these different N species is shown in Figure 4c.…”

Waste wool derived nitrogen-doped hierarchical porous carbon for selective CO2 capture

“…6e, the calculated Q st for WNPC-3 is in the range of 27-13 kJ mol À1 , with the CO 2 uptake varying from 0.05 to 2.7 mmol g À1 . At low CO 2 loading, the high initial Q st value leads to a preferential adsorption of CO 2 over N 2 , which can be attributed to the CO 2 molecules being selectively adsorbed on the surface active nitrogen sites 15,16 and the multiple pore wall interactions with CO 2 molecules. 6,13 At high CO 2 loading, as the active nitrogen sites and microporous surface became gradually saturated, the availability of sorption sites progressively decreased, leading to a lowering in the adsorption heat.…”

“…In comparison to chemical absorption, physical adsorption based on solid adsorbents is regarded as an alternative method. Varieties of solid absorbents including silica, 9 metal-organic frameworks (MOFs), [10][11][12] organic polymers, 13 zeolites 14 and porous carbon materials 15,16 have become the focus for CO 2 capture research. Among them, porous carbon materials have attracted much attention due to their features of large surface area, high porosity, chemical and thermal stability, hydrophobicity and no toxicity, and they are regarded as the most promising CO 2 capture materials.…”

“…Among them, porous carbon materials have attracted much attention due to their features of large surface area, high porosity, chemical and thermal stability, hydrophobicity and no toxicity, and they are regarded as the most promising CO 2 capture materials. [15][16][17][18][19] As is well known, carbon adsorbents with remarkable CO 2 capacity are commonly those possessing large specic surface areas and hierarchical porous architectures with abundant ne micropores (<1 nm) and complementary mesopores, in which the ne micropores (<1 nm) are important for CO 2 adsorption, while the mesopores are useful for CO 2 diffusion. [20][21][22] Meanwhile, due to the fact that CO 2 is weakly acidic, nitrogen elements can be introduced into the carbon frameworks.…”