Wan Liu, Wang Jianlong, Feng Chong, Sun Yahui, Li Kaixi
Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, P. R. China.
Nanoscale. 2015 Apr 21;7(15):6534-44. doi: 10.1039/c4nr07409b.
Nitrogen-rich porous carbons (NPCs) were synthesized from 1,5-dihydroxynaphthalene, urea, and formaldehyde based on benzoxazine chemistry by a soft-templating method with KOH chemical activation. They possess high surface areas of 856.8-1257.8 m(2) g(-1), a large pore volume of 0.15-0.65 cm(3) g(-1), tunable pore structure, high nitrogen content (5.21-5.32 wt%), and high char yields. The amount of the soft-templating agent F127 has multiple influences on the textural and chemical properties of the carbons, affecting the surface area and pore structure, impacting the compositions of nitrogen species and resulting in an improvement of the CO2 capture performance. At 1 bar, high CO2 uptake of 4.02 and 6.35 mmol g(-1) at 25 and 0 °C was achieved for the sample NPC-2 with a molar ratio of F127:urea = 0.010:1. This can be attributed to its well-developed micropore structure and abundant pyridinic nitrogen, pyrrolic nitrogen and pyridonic nitrogen functionalities. The sample NPC-2 also exhibits a remarkable selectivity for CO2/N2 separation and a fast adsorption/desorption rate and can be easily regenerated. This suggests that the polybenzoxazine-based NPCs are desirable for CO2 capture because of possessing a high micropore surface area, a large micropore volume, appropriate pore size distribution, and a large number of basic nitrogen functionalities.
基于苯并恶嗪化学，通过软模板法结合KOH化学活化，由1,5 - 二羟基萘、尿素和甲醛合成了富氮多孔碳（NPCs）。它们具有856.8 - 1257.8 m² g⁻¹的高比表面积、0.15 - 0.65 cm³ g⁻¹的大孔容、可调节的孔结构、高氮含量（5.21 - 5.32 wt%）以及高焦炭产率。软模板剂F127的用量对碳材料的结构和化学性质有多重影响，影响比表面积和孔结构，影响氮物种的组成，并导致二氧化碳捕获性能的提高。在1 bar下，对于F127与尿素摩尔比为0.010:1的样品NPC - 2，在25℃和0℃时分别实现了4.02和6.35 mmol g⁻¹的高二氧化碳吸附量。这可归因于其发达的微孔结构以及丰富的吡啶氮、吡咯氮和吡啶酮氮官能团。样品NPC - 2还表现出对二氧化碳/氮气分离的显著选择性以及快速的吸附/解吸速率，并且易于再生。这表明基于聚苯并恶嗪的NPCs因其具有高微孔表面积、大微孔体积、合适的孔径分布以及大量碱性氮官能团而适用于二氧化碳捕获。
