Precise Single-Step Electrophoretic Multi-Sized Fractionation of Liquid-Exfoliated Nanosheets

Transition metal dichalcogenides (TMDs) 2D nanomaterials' integration into the industry has been hampered by the ability to mass produce nanosheets of designed sizes. Large-scale exfoliation is possible with liquid-phase exfoliation, but precise subsequent isolation of a specified size dimension has yet to be realized. Herein, a precise and efficient method for both size fractionation and nanosheet retrieval is demonstrated using electrophoretic isolation of MoS2 nanosheets in low melting agarose. This can be applied to find out the relative size distribution and sizes within a sample of MoS2. Fractionation can be estimated visually by the relative spread of sizes based on their banding within the agarose. The additional degrees of freedom conferred by the agarose allow for more precise design and control over the size selection process. This serves as a quick and easy method of discerning and isolating the desired size range of MoS2 for further downstream applications in a single step. Nanosheets separated by the procedure retain their structural properties and display size dependency shown empirically and theoretically. This technique is versatile and can be varied according to the needs. It may truly bring large-scale isolation that much needed step closer to industrial scale production.