Considering the limitations of indoor ventilation owing to air pollution, CO2 concentration rises rapidly to 3000 ppm, which is a level that can affect human health. It is essential to develop materials to reduce naturally occurring CO2 in the buildings. Herein, a nano-encapsulated solvent (NES) via Pickering emulsion is proposed for indoor CO2 capture. NaOH aqueous solution is wrapped with hydrophobic surface-functionalized SiO2 (HS-SiO2) nanoparticles, and the corrosiveness of NaOH is not caused by HS-SiO2 wall. CO2 capture capacity of NES-NaOH is evaluated as 7.57 mmol-CO2/g-solvent which is the highest compared to other solvents including metal-organic frameworks (MOFs); it exhibits excellent structural stability in terms of temperature, time, moisture, and CO2 reaction. NES-NaOH presents high selectivity toward CO2 molecules due to the characteristics of NaOH with high gas permeability of macroporous silica wall and it is dispersed in a silicone oil harmless to human body. It is concluded that NES-NaOH can be successfully applied to air purifier filter to control the CO2 concentration in buildings.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (Grant number: 2019R1A2B5B03069991 and No. 2020R1A5A118153 ).
© 2021 Elsevier Ltd
- CO capture filter
- Indoor CO capture
- NaOH aqueous solution
- Nano-encapsulated solvent
- Pickering emulsion
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Waste Management and Disposal
- Process Chemistry and Technology