Ligand Conjugation of Chemically Exfoliated MoS₂

Abstract

MoS2 is a two-dimensional material that is gaining prominence due to its unique electronic and chemical properties. Here, we demonstrate ligand conjugation of chemically exfoliated MoS2 using thiol chemistry. Using this method, we modulate the zeta-potential and colloidal stability of MoS2 sheets through ligand designs, thus enabling its usage as a selective artificial protein receptor for β-galactosidase. The facile thiol functionalization route opens the door for surface modifications of solution processable MoS2 sheets.

Functionalization of Two‐Dimensional Transition‐Metal Dichalcogenides

“…[35] They reacted ce-1T-MoS 2 with bi-functional polyethyleneglycol (peg) molecules (one end of the polyether contained a thiol and the other end a hydroxyl, carboxylate, or ammonium functionality). Upon reaction between the ce-1T-MoS 2 and the organic thiol a marked change in the zeta-potential of the TMD nanosheets was observed, indicating a change in the ce-1T-MoS 2 surface…”

“…This method essentially mirrors Dravid's method, [35] where the [Li Yuan Hu also employed the 'ligand conjugation' approach to functionalizing ce-1T-MoS 2 with silicates. [38] ce-1T-MoS 2 was reacted with dithioglycol using the Dravid method.…”

“…[38] ce-1T-MoS 2 was reacted with dithioglycol using the Dravid method. [35] The authors propose that this functionalization method yields Cai, Liu, and co-workers reported the preparation of iron oxide decorated ce-1T-MoS 2 nanosheets employing the 'ligand conjugation' technique. [39] In this instance, meso-2,3-dimercaptosuccinic acid (Figure 3) coated iron oxide nanoparticles were reacted with ce-1T-MoS 2 using the Dravid method.…”

“…[39] In this instance, meso-2,3-dimercaptosuccinic acid (Figure 3) coated iron oxide nanoparticles were reacted with ce-1T-MoS 2 using the Dravid method. [35] It was postulated that the dithiol of the meso-2,3-dimercaptosuccinic acid was filling S-atom vacancies on the ce-1T-MoS 2 surface, however as with the other 'ligand conjugation' methods no evidence to support this postulate was provided. The iron-oxide decorated ce-1T-MoS 2 was then further coated with polyethylene glycol to make the nanomaterials stable under physiological conditions.…”

Post‐Graphene 2D Chemistry: The Emerging Field of Molybdenum Disulfide and Black Phosphorus Functionalization

“…As outlined, it has early been observed that the n ‐butyllithium promoted exfoliation of MoS 2 , which involves also an ultrasonication step, leads also to the formation of defects (mainly described as sulfur vacancies) 19, 21b, 31a, 69. This on the other hand provided the basis for one of the initial covalent functionalization approaches for MoS 2 .…”