Upscaled Synthesis Protocol for Phase-Pure, Colloidally Stable MXenes with Long Shelf LivesShow others and affiliations
2023 (English)In: Small Methods, E-ISSN 2366-9608Article in journal (Refereed) Epub ahead of print
Abstract [en]
MXenes are electrically conductive 2D transition metal carbides/nitrides obtained by the etching of nanolaminated MAX phase compounds, followed by exfoliation to single- or few-layered nanosheets. The mainstream chemical etching processes have evolved from pure hydrofluoric acid (HF) etching into the innovative "minimally intensive layer delamination" (MILD) route. Despite their current popularity and remarkable application potential, the scalability of MILD-produced MXenes remains unproven, excluding MXenes from industrial applications. This work proposes a "next-generation MILD" (NGMILD) synthesis protocol for phase-pure, colloidally stable MXenes that withstand long periods of dry storage. NGMILD incorporates the synergistic effects of a secondary salt, a richer lithium (Li) environment, and iterative alcohol-based washing to achieve high-purity MXenes, while improving etching efficiency, intercalation, and shelf life. Moreover, NGMILD comprises a sulfuric acid (H2SO4) post-treatment for the selective removal of the Li3AlF6 impurity that commonly persists in MILD-produced MXenes. This work demonstrates the upscaled NGMILD synthesis of (50 g) phase-pure Ti(3)C(2)Tz MXene clays with high extraction yields (>22%) of supernatant dispersions. Finally, NGMILD-produced MXene clays dry-stored for six months under ambient conditions experience minimal degradation, while retaining excellent redispersibility. Overall, the NGMILD protocol is a leap forward toward the industrial production of MXenes and their subsequent market deployment.
Place, publisher, year, edition, pages
WILEY-V C H VERLAG GMBH , 2023.
Keywords [en]
2D ceramics; chemical exfoliation; colloidal stability; degradation resistance; MXenes oxidation; surface engineering; upscaling
National Category
Organic Chemistry
Identifiers
URN: urn:nbn:se:liu:diva-198821DOI: 10.1002/smtd.202300776ISI: 001079954400001PubMedID: 37806774OAI: oai:DiVA.org:liu-198821DiVA, id: diva2:1808231
Note
Funding Agencies|N.G. thanks the Fund for Scientific Research Flanders (FWO-Vlaanderen) for his Ph.D. fellowship for fundamental research No 1118120N and travel grant K208923N enabling a visiting scholarship at Texas Aamp;M University for performing the XPS measurements. [1118120N, K208923N, KA/20/037]; Fund for Scientific Research Flanders; Swedish Research Council [2021-00171, RIF21-0026]; Foundation for Strategic Research for access to ARTEMI
2023-10-302023-10-302023-10-30