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Abstract Porous MXene-polymer composites have gained attention due to their low density, large surface area, and high electrical conductivity, which can be used in applications such as electromagnetic interference shielding, sensing, energy storage, and catalysis. High internal phase emulsions (HIPEs) can be used to template the synthesis of porous polymer structures, and when solid particles are used as the interfacial agent, composites with pores lined with the particles can be realized. Here, we report a simple and scalable method to prepare conductive porous MXene/polyacrylamide structures via polymerization of the continuous phase in oil/water HIPEs. The HIPEs are stabilized by salt flocculated Ti 3 C 2 T x nanosheets, without the use of a co-surfactant. After polymerization, the polyHIPE structure consists of porous polymer struts and pores lined with Ti 3 C 2 T x nanosheets, as confirmed by scanning electron microscopy, energy dispersive x-ray spectroscopy, and x-ray photoelectron spectroscopy. The pore size can be tuned by varying the Ti 3 C 2 T x concentration, and the interconnected Ti 3 C 2 T x network allows for electrical percolation at low Ti 3 C 2 T x loading; further, the electrical conductivity is stable for months indicating that in these composites, the nanosheets are stable to oxidation at ambient conditions. The polyHIPEs also exhibit rapid radio frequency heating at low power (10 °C s −1 at 1 W). This work demonstrates a simple approach to accessing electrically conductive porous MXene/polymer composites with tunable pore morphology and good oxidation stability of the nanosheets.
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Architecting MXenes in polymer composites
The major challenge to fabricate MXene/polymer composites are the processing conditions and poor control over the distribution of the MXene nanosheets within the polymer matrix. Traditional ways involve the direct mix of fillers and polymers to form a random homogeneous composite, which leads to inefficient use of fillers. To address these challenges, researchers have focused on the development of ordered MXene/polymer composite structures using various fabrication strategies. In this review, we summarize recent advances of structured MXene/polymer composites and their processing-structure-property relationships. Two main forms of MXene/polymer composites (films and foams) are separately discussed with a focus on the detailed fabrication means and corresponding structures. These architected composites complement those in which MXenes nanosheets are isotropically dispersed throughout, such as those formed by aqueous solution mixing approaches. This review culminates in a perspective on the future opportunities for architected MXene/polymer composites.
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- PAR ID:
- 10529171
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Progress in Polymer Science
- Volume:
- 153
- Issue:
- C
- ISSN:
- 0079-6700
- Page Range / eLocation ID:
- 101830
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.progpolymsci.2024.101830
