Mechanisms of carbon capture using Li4SiO4 nanoparticles

https://doi.org/10.1039/C6TA06133H

“Schematic illustrations comparing the carbon dioxide sorption and desorption mechanisms of Li₄SiO₄ nanoparticles and the newly developed nano rods, as well the influence of particle morphology on their durability are provided in Fig. 3a and b. The small thickness of the nanorods enables fast absorption kinetics just as in the case of nanoparticles. The better durability of the nanorod sample is highlighted based on ceramic sintering and particle coalescence mechanisms. It is well known that in liquid phase assisted sintering, the densification is achieved by the rearrangement and shape changes of the particles. Rearrangement is strongly affected by the size and morphology of the particles. Spherical and mono-dispersed particles are advantageous for particle rearrangement and sintering while particles like nanorods, having a high aspect ratio, are difficult to sinter. The Ostwald ripening/particle coalescence process invariably results in a reduction of the total surface area of the particles.^31,32 Hence the particle coarsening process as shown in Fig. 3b of the schematic always leads to a reduction in absorption kinetics owing to the reduction of the absorbent–gas interface available for chemisorption. In contrast, the use of higher aspect ratio Li₄SiO₄ nanorods impedes coalescence and agglomerate formation due to which it is possible to maintain high absorption kinetics even after several absorption/desorption cycles. The effects of morphological tuning on the kinetics of the carbon dioxide absorption process as well as the durability of the resulting particles are clearly depicted in the illustration.”

“Fig. 3 Schematic illustrations comparing the carbon dioxide absorption and desorption mechanisms and the durability of (a) the newly developed Li₄SiO₄ nanorods and (b) commonly found Li₄SiO₄ nanoparticles.”