Carbon dioxide adsorption on nano/micro-scale porous adsorbents. (2016)

• Record Type: Journal Article
• Authors: Chiang, Yu-Chun; Hsu, Wei-Lien
• Is Part Of: International journal of nanomanufacturing. Volume 12:Number 1(2016)
• Page Start: 1
• Page End: 14
• Publication Date: 2016
• Subjects: carbon adsorption -- carbon dioxide -- CO2 -- activated carbon fibres -- ACFs -- porous adsorbents -- surface chemistry -- adsorption capacity -- nanoscale adsorbents -- micro-scale adsorbents -- nanotechnology -- carbon nanotubes -- CNTs -- chemical vapour deposition -- CVD -- exothermic reaction -- nitrogen doping -- pyridine-like structures -- hydrophobicity; Nanostructured materials industry -- Periodicals; Nanotechnology -- Periodicals; 620.505
• Languages: English
• ISSNs: 1746-9392

Abstract

The objective of this paper is to investigate the physicochemical properties of the composites, carbon nanotubes (CNTs)/activated carbon fibres (ACFs), and determine the adsorption capacity of CO2 on CNTs/ACFs. The chemical vapour deposition method was used for growth of CNTs without or with nitrogen doping. The spaghetti-like and a little randomly oriented CNTs with a high density and homogeneity were observed to grow onto the ACFs, while the morphology of nitrogen-doped CNTs on ACFs looked short, coarse and entangled. The result of high resolution of XPS N1s peak showed that the pyridine-type N and quaternary N were the predominant functional groups on all samples. Specifically, nitrogen-doped CNTs were characterised by the pyridine-like structures of six-member rings and hydrophobicity due to deficiency of oxygen atoms. The adsorption capacities of CO2 on all samples decreased gradually as the temperature increased, implying the exothermic reaction on adsorption. The adsorption capacities of CO2 based on surface areas at 25°C and 1 bar were between 1.60-2.69 µmole/m 2, and the ACFs grafted with nitrogen-doped CNTs exhibited the best performance for CO2 adsorption.