Fibrillation of Pristine 2D Materials by 2D‐Confined Electrolytes

• Published in: Advanced functional materials Vol. 34; no. 29
• Main Authors: Tan, Hui Li, Donato, Katarzyna Z., Costa, Mariana C. F., Carvalho, Alexandra, Trushin, Maxim, Ng, Pei Rou, Yau, Xin Hui, Koon, Gavin K. W., Tolasz, Jakub, Němečková, Zuzana, Ecorchard, Petra, Donato, Ricardo K., Neto, Antonio H. Castro
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.07.2024
• Subjects: Basal plane; boron nitride; Crystal structure; Electrolytes; fiber; Flakes; graphene; Interlayers; Molten salt electrolytes; MoS2; Nanomaterials; Organic salts; Polyelectrolytes; scrolling; self‐assembly; Solid electrolytes; Solvation; Thickness; Two dimensional materials
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202315038

2D materials are solid microscopic flakes with a‐few‐Angstrom thickness possessing some of the largest surface‐to‐volume ratios known. Altering their conformation state from a flat flake to a scroll or fiber offers a synergistic association of properties arising from 2D and 1D nanomaterials. However, a combination of the long‐range electrostatic and short‐range solvation forces produces an interlayer repulsion that has to be overcome, making scrolling 2D materials without disrupting the pristine structure a challenging task. Herein, a facile method is presented to alter the 2D materials’ inter‐layer interactions by confining organic salts onto their basal area, forming 2D‐confined electrolytes. The confined electrolytes produce local charge inhomogeneities, which can conjugate across the interlayer gap, binding the two surfaces. This allows the 2D‐confined electrolytes to behave as polyelectrolytes within a higher dimensional order (2D → 1D) and form robust nanofibers with distinct electronic properties. The method is not material‐specific and the resulting fibers are tightly bound even though the crystal structure of the basal plane remains unaltered. The strong non‐covalent attachment of electrolytic species onto the 2D materials’ basal plane alters their interlayer interactions, allowing for scrolling and self‐assembly into sturdy fibers without disrupting the pristine crystalline structure.