Foaming Effect of a Polymer Precursor with a Low N Content on Fabrication of N-Doped Porous Carbons for CO₂ Capture

Abstract

Because of their sufficient surface areas, developed porosities, and high stabilities, N-doped porous carbons (NDPCs) have presented an excellent CO2 adsorption ability. NDPCs are usually fabricated through the carbonization of N-containing polymers. The effect of N species enlarging surface areas and foaming pores has been confirmed. However, traditional polymer precursors of NDPCs must have a relatively high N content and give unsatisfactory structural characters and CO2 capacities of their NDPCs. In this study, an NDPC precursor code-named NUT-50-EDA with a N content of only 6.4 wt % is prepared, while the amino groups in the precursor still play a significant role in the porogen during the carbonization process. The generated NDPCs show more abundant micropores, larger surface areas, and higher CO2 adsorption capacities compared to those of the counterpart porous carbons (PCs) made from the precursor without ammonification. With a relatively low N content (1.5 wt %), NDPC-700 with a large surface area of 1620 m2/g, obtained by carbonization treatment of NUT-50-EDA at 700 °C, still displays an outstanding CO2 uptake of 6.4 mmol/g at 0 °C and 1 bar, compared with other reported benchmarks. This work demonstrates that NUT-50-EDA, possessing a highly effective pore-foaming agent of N species, can be utilized as the ideal precursor for improving the porosities and CO2 capacities of its NDPCs.

Modulated Hydrothermal Synthesis of Highly Stable MOF-808(Hf) for Methane Storage

“…24,30,66 Because of having a higher surface area, MOF-808(Zr) has a higher CO 2 uptake capacity (1.61 mmol g −1 ) than that of MOF-808(Hf) (1.45 mmol g −1 , Figure 6c, Table S3). The CO 2 uptake capacity is much higher than polymeric ionic liquid PAPIL-2 (0.15 mmol g −1 ) 67 and PIM-1 (1.66 mmol g −1 ) 68 but fairly lower than NDPC-700 (3.8 mmol g −1 ), 69 SIFSIX-2-Cu-i (∼2.39 mmol g −1 ), 70 Mg 2 (dobdc)-(N 2 H 4 ) 2 (∼5.18 mmol g −1 ), 71 and Mg 2 (dobdc) (∼5.91 mmol g −1 ). 72 However, MOF-808(Zr) shows a comparable CO 2 uptake capacity to that of UiO-66(Zr) (1.79 mmol g −1 ) despite its higher BET surface area, 73 indicating its weaker interactions due to the enlarged pore size unfavorable for low-pressure gas storage applications.…”

Constructing Hierarchically Porous N-Doped Carbons Derived from Poly(ionic liquids) with the Multifunctional Fe-Based Template for CO2 Adsorption

“…The ideal adsorption solution theory (IAST) was applied to determine the CO 2 /N 2 selectivity, which was crucial for practical applications. , In Figure d, the N 2 adsorption capacity of NDPC-1-800 was much lower than its CO 2 uptake rather than that of NDPC-1-800 in Figure c, indicating the high CO 2 /N 2 selectivity of NDPC-1-800. Moreover, the dual-site Langmuir–Freundlich (DSLF) model was taken in Figure c,d for fitting the adsorption isotherms of CO 2 and N 2 , which could describe these adsorptions more accurately .…”

Carbon dioxide adsorption based on porous materials

“…17 illustrates the literature of various carbon-based adsorbents along with their surface area used for CO 2 uptake. [167][168][169][170][171][172][173][174][175][176]…”