Pei Yi-Rong, Yang Jae-Hun, Choi Goeun, Choy Jin-Ho
Department of Chemistry and Nanoscience, Ewha Womans University Seoul 03760 Korea.
Global Innovative Center for Advanced Nanomaterials (GICAN), School of Engineering, Faculty of Engineering and Built Environment, The University of Newcastle Callaghan New South Wales 2308 Australia.
RSC Adv. 2020 Feb 13;10(12):6814-6821. doi: 10.1039/c9ra09698a.
Hexagonal and wormhole-type mesoporous geopolymers were developed by controlling the concentration of a structure directing agent (cetrimonium bromide, CTAB) with fixed ratios of Si/Al, KOH/(Si + Al), and HO/(Si + Al), and their detailed porous structures were confirmed by TEM, N adsorption-desorption and X-ray diffraction measurements. The as-prepared geopolymers were then used as templates to replicate porous carbons with various structures and porosities for CO adsorption. To understand the correlation between the CO adsorptivity and porous structures, we tuned the porosity of the geopolymer-templated carbons by modifying the structures of the geopolymers. The porous carbons obtained from the hexagonal-type porous geopolymers were found to be composed of the aggregates of carbon nanowires exhibiting large particles, while those obtained from the wormhole-like porous geopolymers were determined to be wormhole type as well, as evidenced by TEM and X-ray diffraction studies. According to the CO adsorption isotherms of the porous carbons, the aggregates of carbon nanowires exhibited the highest CO adsorptivity due to their highest microporosity and largest specific surface area.
通过在固定的硅铝比、氢氧化钾与（硅 + 铝）的比例以及水与（硅 + 铝）的比例条件下，控制结构导向剂（十六烷基三甲基溴化铵，CTAB）的浓度，制备出了六边形和虫孔型介孔地质聚合物，并通过透射电子显微镜（TEM）、氮气吸附 - 脱附以及X射线衍射测量证实了它们详细的多孔结构。然后将制备好的地质聚合物用作模板，复制出具有各种结构和孔隙率的多孔碳用于二氧化碳吸附。为了理解二氧化碳吸附性与多孔结构之间的相关性，我们通过改变地质聚合物的结构来调节以地质聚合物为模板的碳的孔隙率。由六边形多孔地质聚合物得到的多孔碳被发现是由呈现大颗粒的碳纳米线聚集体组成，而由虫孔状多孔地质聚合物得到的多孔碳经透射电子显微镜和X射线衍射研究证实也是虫孔型。根据多孔碳的二氧化碳吸附等温线，碳纳米线聚集体因其最高的微孔率和最大的比表面积而表现出最高的二氧化碳吸附性。
