Investigation of a power strip-like composite nanoparticle derivative with liquid-like behaviour on capturing carbon dioxide

Abstract

Power strip-like composite nanoparticle derivatives with liquid-like behaviour were prepared without solvent at room temperature (298 K) by employing multi-walled carbon nanotubes (MWCNTs) and silicon dioxide (SiO₂) as a composite core, (3-glycidyloxypropyl) trimethoxysilane (KH-560) with an epoxy group as a corona and the polyetheramine M-2070 as a canopy. The morphology and structure of this nanoparticle organic hybrid material (MWCNT/SiO₂ NOHM) were characterized by a series of techniques, and showed a contrast with NOHMs based on simplex core MWCNTs (MWCNT NOHM) and SiO₂ (SiO₂ NOHM). The MWCNT/SiO₂ NOHM presents a special “power strip” structure, with lower viscosity and more organic chains. The CO₂ capture capacity of MWCNT/SiO₂ NOHM under 0–5 MPa CO₂ pressure at 298 K was investigated. Compared with MWCNT NOHM and SiO₂ NOHM, MWCNT/SiO₂ NOHM showed an improved CO₂ capture capacity via both chemisorption and physisorption. This is owing to the “power strip” structure, which provides more reactive groups that can react with CO₂. In addition, the lower viscosity of MWCNT/SiO₂ NOHM offers larger molecular intervals and weaker intermolecular forces, which make it easier for CO₂ to fill the potential space. The regeneration capacity and adsorption stability of MWCNT/SiO₂ NOHM are great, rendering it a very good potential material for CO₂ adsorption.