Direct air capture (DAC) of CO2is an emerging technology in the battle against climate change. Many sorbent materials and different technologies such as moisture swing sorption have been explored for this application. However, developing efficient scaffolds to adopt promising sorbents with fast kinetics is challenging, and very limited effort has been reported to address this critical issue. In this work, the availability and kinetic uptake of CO2in sorbents embedded in various matrices are studied. Three scaffolds including a commercially available industrial film containing ion‐exchange resin (IER), IER particles embedded in dense electrospun fibers, and IER particles embedded in porous electrospun fibers are compared, in which a solvothermal polymer additive removal technique is used to create porosity in porous fibers. A frequency response technique is developed to measure the uptake capacity, sorbent availability, and kinetic uptake rate. The porous fiber has 90% IER availability, while the dense fibers have 50% particle accessibility. The sorption half time for both electrospun fiber samples is 10 ± 3 min. Our experimental results demonstrate that electrospinning polymer/sorbent composites is a promising technology to facilitate the handleability of sorbent particles and to improve the sorption kinetics, in which the IER embedded in porous electrospun fibers shows the highest cycle capacity with an uptake rate of 1.4 mol CO2per gram‐hour. © 2018 American Institute of Chemical EngineersAIChE J, 65: 214–220, 2019
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Electrospinning of LaB 6 /PEDOT:PSS/PEO Fiber Composites of Unique Morphologies
We present a direct electrospinning fabrication technique for the manufacture of PEDOT:PSS/PEO polymer fibers containing embedded cubic lanthanum hexaboride (LaB6) particles. We focus on the impact of relative humidity on the formation of uniform polymer fibers and show that a relative humidity of 5% is optimal, resulting in an average fiber thickness of 266 ± 88 nm. As the relative humidity is increased, the fibers contain beads as a consequence of Rayleigh instabilities. The addition of lanthanum hexaboride cubic particles to the polymer solution before electrospinning results in the encapsulation of the LaB6 particles inside the fibers. We investigate the effect of LaB6 particle size on morphology and observe that particles of ~500 nm yield a fiber-cube-fiber morphology, while 2 μm particles result in fewer embedded cubes along the length of the polymer fibers. This phenomenon likely arises from electrodynamic interactions between the LaB6 particles in the polymer solution and the electric field lines generated during electrospinning between the spinneret and the collector. Our results display the versatility of the electrospinning technique in the fabrication of unique polymer/hexaboride composite fibers.
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- Award ID(s):
- 2016247
- PAR ID:
- 10657188
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Langmuir
- Volume:
- 40
- Issue:
- 47
- ISSN:
- 0743-7463
- Page Range / eLocation ID:
- 25229 to 25235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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