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Abstract Vanadium carbide (V2CTx) MXene is a 2D nanomaterial widely investigated for energy storage applications due to its superior electrochemical properties. However, V2CTxquickly degrades in water, which limits its performance and longevity. Furthermore, the relationship between V2CTxMXene synthesis parameters and their corresponding aqueous stability is underexplored. In this study, delaminated V2CTxMXene films synthesized with four tetraalkylammonium hydroxide intercalants were characterized for their structural and aqueous stability differences. Delaminated V2CTxMXene d‐spacing, flake edge lengths, and surface morphology were generally dependent on the intercalant radius. Specifically, the intercalant radius exhibited a positive correlation with d‐spacing and a negative correlation with flake edge lengths. These structural differences have direct impacts on the aqueous stability of V2CTx. For example, Raman spectra of each thin film indicated that amorphous carbon formation upon water exposure positively corresponded with flake edge lengths. 3D printed film holders were fashioned to mimic electrochemical cell configurations to evaluate vanadium dissolution from each film when exposed to water. Vanadium dissolution from each film was statistically similar (i.e., no correlation with intercalant radius) and substantial (i.e., ppm concentration range). These findings will benefit aqueous applications of V2CTxMXenes, where material degradation and vanadium release may impact MXene performance.
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Mechanical behavior of MXene-Polymer layered nanocomposite using computational finite element analysis
The structural integrity of MXene and MXene-based materials is important across applications from sensors to energy storage. While MXene processing has received significant attention, its structural integrity for real-world applications remains challenging due to its flake-like structure. Here the mechanical response of layered MXene-polymer nanocomposites (MPC) with high MXene concentration (>70 %) and bioinspired nacre-like brick-and-mortar architecture is investigated to offer insights for MPC design and processing. An automated finite element analysis (FEA) framework is developed to analyze MPC models with randomized geometries and multiple combinations of the parameter space. Specifically, the influence of concentration, aspect ratio (AR), flake thickness, flake distribution, and interfacial strength is investigated. The results reveal property trends such as increasing elastic modulus, strength, and toughness with increasing cohesive strength and concentration for lower AR (=40, 60) but a decreasing trend at higher AR of 75. Local structural features like flake distribution, overlapping MXene lengths, and interconnected polymers in adjacent layers was found a critical determinant of performance. For example, stronger cohesive interaction showed 6X high toughness (291 226 ) compared to weaker case (50 24 ), but the large scatter highlighted the impact of microstructural features. The results are compared and validated with theoretical, computational, and experimental work. The findings provide valuable guidance for optimizing MPC design and their processing. Finally, the automation of the framework allows the design to be extended beyond the current system and chosen material combinations.
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- Award ID(s):
- 2304788
- PAR ID:
- 10528758
- Publisher / Repository:
- Composites Part B: Engineering
- Date Published:
- Journal Name:
- Composites Part B: Engineering
- Volume:
- 284
- Issue:
- C
- ISSN:
- 1359-8368
- Page Range / eLocation ID:
- 111689
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.compositesb.2024.111689
