Li Yao, Cao Minhua
Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion Materials, Department of Chemistry, Beijing Institute of Technology, Beijing, 100081, P.R. China.
Chem Asian J. 2015 Jul;10(7):1496-504. doi: 10.1002/asia.201500185. Epub 2015 May 29.
Sustainable carbon materials have received particular attention in CO2 capture and storage owing to their abundant pore structures and controllable pore parameters. Here, we report high-surface-area hierarchically porous N-doped carbon microflowers, which were assembled from porous nanosheets by a three-step route: soft-template-assisted self-assembly, thermal decomposition, and KOH activation. The hydrazine hydrate used in our experiment serves as not only a nitrogen source, but also a structure-directing agent. The activation process was carried out under low (KOH/carbon=2), mild (KOH/carbon=4) and severe (KOH/carbon=6) activation conditions. The mild activated N-doped carbon microflowers (A-NCF-4) have a hierarchically porous structure, high specific surface area (2309 m(2) g(-1)), desirable micropore size below 1 nm, and importantly large micropore volume (0.95 cm(3) g(-1)). The remarkably high CO2 adsorption capacities of 6.52 and 19.32 mmol g(-1) were achieved with this sample at 0 °C (273 K) and two pressures, 1 bar and 20 bar, respectively. Furthermore, this sample also exhibits excellent stability during cyclic operations and good separation selectivity for CO2 over N2.
由于其丰富的孔结构和可控的孔参数，可持续碳材料在二氧化碳捕获和储存方面受到了特别关注。在此，我们报道了高比表面积的分级多孔氮掺杂碳微花，其通过三步路线由多孔纳米片组装而成：软模板辅助自组装、热分解和KOH活化。我们实验中使用的水合肼不仅作为氮源，还作为结构导向剂。活化过程在低（KOH/碳=2）、中（KOH/碳=4）和高（KOH/碳=6）活化条件下进行。中度活化的氮掺杂碳微花（A-NCF-4）具有分级多孔结构、高比表面积（2309 m² g⁻¹）、理想的小于1 nm的微孔尺寸，重要的是具有大的微孔体积（0.95 cm³ g⁻¹）。该样品在0 °C（273 K）和1 bar及20 bar两个压力下分别实现了6.52和19.32 mmol g⁻¹的极高二氧化碳吸附容量。此外，该样品在循环操作过程中还表现出优异的稳定性以及对二氧化碳相对于氮气的良好分离选择性。
