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Abstract The chemical stability of 2D MXene nanosheets in aqueous dispersions must be maintained to foster their widespread application. MXene nanosheets react with water, which results in the degradation of their 2D structure into oxides and carbon residues. The latter detrimentally restricts the shelf life of MXene dispersions and devices. However, the mechanism of MXene degradation in aqueous environment has yet to be fully understood. In this work, the oxidation kinetics is investigated of Ti3C2Txand Ti2CTxin aqueous media as a function of initial pH values, ionic strengths, and nanosheet concentrations. The pH value of the dispersion is found to change with time as a result of MXene oxidation. Specifically, MXene oxidation is accelerated in basic media by their reaction with hydroxyl anions. It is also demonstrated that oxidation kinetics are strongly dependent on nanosheet dispersion concentration, in which oxidation is accelerated for lower MXene concentrations. Ionic strength does not strongly affect MXene oxidation. The authors also report that citric acid acts as an effective antioxidant and mitigates the oxidation of both Ti3C2Txand Ti2CTxMXenes. Reactive molecular dynamic simulations suggest that citric acid associates with the nanosheet edge to hinder the initiation of oxidation.
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This content will become publicly available on August 21, 2026
Computational evaluation of structural and chemical possibilities exposed by Ti 2 CT x nanoribbons and 2D-nanoparticles
MXenes are a rapidly expanding family of 2D materials known for their unique tunability, yet studies of their edges remain sparse compared to their better-characterized basal planes.
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- Award ID(s):
- 2318105
- PAR ID:
- 10633638
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 17
- Issue:
- 33
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 19210 to 19219
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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