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Title: Carbon capture in polymer-based electrolytes
Nanoparticle organic hybrid materials (NOHMs) have been proposed as excellent electrolytes for combined CO2capture and electrochemical conversion due to their conductive nature and chemical tunability. However, CO2capture behavior and transport properties of these electrolytes after CO2capture have not yet been studied. Here, we use a variety of nuclear magnetic resonance (NMR) techniques to explore the carbon speciation and transport properties of branched polyethylenimine (PEI) and PEI-grafted silica nanoparticles (denoted as NOHM-I-PEI) after CO2capture. Quantitative13C NMR spectra collected at variable temperatures reveal that absorbed CO2exists as carbamates (RHNCOO−or RR′NCOO−) and carbonate/bicarbonate (CO32−/HCO3−). The transport properties of PEI and NOHM-I-PEI studied using1H pulsed-field-gradient NMR, combined with molecular dynamics simulations, demonstrate that coulombic interactions between negatively and positively charged chains dominate in PEI, while the self-diffusion in NOHM-I-PEI is dominated by silica nanoparticles. These results provide strategies for selecting adsorbed forms of carbon for electrochemical reduction.  more » « less
Award ID(s):
1927325
PAR ID:
10536360
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
16
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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